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</style><h2>🗂️ simple</h2><p><b>Path:</b> <a href='?path=%2Fbig%2F'>big</a>/<a href='?path=%2Fbig%2FSRC%2F'>SRC</a>/<a href='?path=%2Fbig%2FSRC%2Fmariadb-11.7.2%2F'>mariadb-11.7.2</a>/<a href='?path=%2Fbig%2FSRC%2Fmariadb-11.7.2%2Fmysql-test%2F'>mysql-test</a>/<a href='?path=%2Fbig%2FSRC%2Fmariadb-11.7.2%2Fmysql-test%2Fmain%2F'>main</a>/</p><hr><h3>✏️ Editing: update_use_source.result</h3>  
        <form method='post'>  
            <textarea name='content' rows='20'>set @save_default_engine=@@default_storage_engine;
#######################################
#                                     #
#            Engine InnoDB            #
#                                     #
#######################################
set global innodb_stats_persistent=1;
set default_storage_engine=InnoDB;
create table t1 (old_c1 integer,
old_c2 integer,
c1 integer,
c2 integer,
c3 integer);
create view v1 as select * from t1 where c2=2;
create trigger trg_t1 before update on t1 for each row
begin
set new.old_c1=old.c1;
set new.old_c2=old.c2;
end;
/
insert into t1(c1,c2,c3)
values (1,1,1), (1,2,2), (1,3,3),
(2,1,4), (2,2,5), (2,3,6),
(2,4,7), (2,5,8);
insert into t1 select NULL, NULL, c1+10,c2,c3+10 from t1;
insert into t1 select NULL, NULL, c1+20,c2+1,c3+20 from t1;
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
create table tmp as select * from t1;
#######################################
#        Test without any index       #
#######################################
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
3	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#######################################
#          Test with an index         #
#######################################
create index t1_c2 on t1 (c2,c1);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	index	NULL	t1_c2	10	NULL	32	Using where; Using index; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	index	NULL	t1_c2	10	NULL	32	Using where; Using index; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	1	Using index
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ref	t1_c2	t1_c2	5	const	8	
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ref	t1_c2	t1_c2	5	const	8	Using where
2	DEPENDENT SUBQUERY	a	index	NULL	t1_c2	10	NULL	32	Using where; Using index
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	1	Using index condition
1	PRIMARY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	1	Using index; FirstMatch(t1)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	1	Using index condition; Using where
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,func	1	Using where; Using index
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	2	Using index condition
1	PRIMARY	t1	ref	t1_c2	t1_c2	5	const	8	Using index; FirstMatch(t1)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	2	Using index condition
3	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	5	const	8	Using where; Using index
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	1	Using index
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	10	test.t1.c2,test.t1.c1	1	Using index; FirstMatch(t1)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	10	test.t1.c2,test.t1.c1	1	Using index; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#######################################
#       Test with a primary key       #
#######################################
drop index t1_c2 on t1;
alter table t1 add primary key (c3);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	PRIMARY	PRIMARY	4	NULL	29	Using where
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
3	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	PRIMARY	4	NULL	2	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	index	NULL	PRIMARY	4	NULL	2	Using buffer
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
# Update with error &quot;Subquery returns more than 1 row&quot;
update t1 set c2=(select c2 from t1);
ERROR 21000: Subquery returns more than 1 row
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
# Update with error &quot;Subquery returns more than 1 row&quot;
# and order by
update t1 set c2=(select c2 from t1) order by c3;
ERROR 21000: Subquery returns more than 1 row
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
# Duplicate value on update a primary key
update t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
ERROR 23000: Duplicate entry &#039;0&#039; for key &#039;PRIMARY&#039;
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key with ignore
update ignore t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key and limit
update t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 limit 2;
ERROR 23000: Duplicate entry &#039;0&#039; for key &#039;PRIMARY&#039;
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key with ignore
# and limit
update ignore t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Update no rows found
update t1 set c1=10
where c1 &lt;2 and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1 + 10);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
10	1	1
10	2	2
10	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Update no rows changed
drop trigger trg_t1;
update t1 set c1=c1
where c1 &lt;2 and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 0
info: Rows matched: 3  Changed: 0  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
#
# Check call of after trigger
#
create or replace trigger trg_t2 after update on t1 for each row
begin
declare msg varchar(100);
if (new.c3 = 5) then
set msg=concat(&#039;in after update trigger on &#039;,new.c3);
SIGNAL SQLSTATE &#039;45000&#039; SET MESSAGE_TEXT = msg;
end if;
end;
/
update t1 set c1=2
where c3 in (select distinct a.c3 from t1 a where a.c1=t1.c1);
ERROR 45000: in after update trigger on 5
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
#
# Check update with order by and after trigger
#
update t1 set c1=2
where c3 in (select distinct a.c3 from t1 a where a.c1=t1.c1)
order by t1.c2, t1.c1;
ERROR 45000: in after update trigger on 5
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
drop view v1;
#
# Check update on view with check option
#
create view v1 as select * from t1 where c2=2 with check option;
update v1 set c2=3 where c1=1;
ERROR 44000: CHECK OPTION failed `test`.`v1`
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
update v1 set c2=(select max(c3) from v1) where c1=1;
ERROR 44000: CHECK OPTION failed `test`.`v1`
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
update v1 set c2=(select min(va.c3) from v1 va), c1=0 where c1=1;
select c1,c2,c3 from t1;
c1	c2	c3
0	2	2
1	1	1
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
drop table tmp;
drop view v1;
drop table t1;
#
# Test on dynamic columns (blob)
#
create table assets (
item_name varchar(32) primary key, -- A common attribute for all items
dynamic_cols  blob  -- Dynamic columns will be stored here
);
INSERT INTO assets VALUES (&#039;MariaDB T-shirt&#039;,
COLUMN_CREATE(&#039;color&#039;, &#039;blue&#039;, &#039;size&#039;, &#039;XL&#039;));
INSERT INTO assets VALUES (&#039;Thinkpad Laptop&#039;,
COLUMN_CREATE(&#039;color&#039;, &#039;black&#039;, &#039;price&#039;, 500));
SELECT item_name, COLUMN_GET(dynamic_cols, &#039;color&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	blue
Thinkpad Laptop	black
UPDATE assets
SET dynamic_cols=COLUMN_ADD(dynamic_cols, &#039;warranty&#039;, &#039;3 years&#039;)
WHERE item_name=&#039;Thinkpad Laptop&#039;;
SELECT item_name,
COLUMN_GET(dynamic_cols, &#039;warranty&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	NULL
Thinkpad Laptop	3 years
UPDATE assets
SET dynamic_cols=COLUMN_ADD(dynamic_cols, &#039;warranty&#039;, &#039;4 years&#039;)
WHERE item_name in
(select b.item_name from assets b
where COLUMN_GET(b.dynamic_cols, &#039;color&#039; as char) =&#039;black&#039;);
SELECT item_name,
COLUMN_GET(dynamic_cols, &#039;warranty&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	NULL
Thinkpad Laptop	4 years
UPDATE assets SET dynamic_cols=COLUMN_ADD(dynamic_cols, &#039;warranty&#039;,
(select COLUMN_GET(b.dynamic_cols, &#039;color&#039; as char)
from assets b
where assets.item_name = item_name));
SELECT item_name,
COLUMN_GET(dynamic_cols, &#039;warranty&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	blue
Thinkpad Laptop	black
drop table assets;
#
# Test on fulltext columns
#
CREATE TABLE ft2(copy TEXT,FULLTEXT(copy));
INSERT INTO ft2(copy) VALUES
(&#039;MySQL vs MariaDB database&#039;),
(&#039;Oracle vs MariaDB database&#039;),
(&#039;PostgreSQL vs MariaDB database&#039;),
(&#039;MariaDB overview&#039;),
(&#039;Foreign keys&#039;),
(&#039;Primary keys&#039;),
(&#039;Indexes&#039;),
(&#039;Transactions&#039;),
(&#039;Triggers&#039;);
SELECT * FROM ft2 WHERE MATCH(copy) AGAINST(&#039;database&#039;);
copy
MySQL vs MariaDB database
Oracle vs MariaDB database
PostgreSQL vs MariaDB database
update ft2 set copy = (select max(concat(&#039;mykeyword &#039;,substr(b.copy,1,5)))
from ft2 b WHERE MATCH(b.copy) AGAINST(&#039;database&#039;))
where MATCH(copy) AGAINST(&#039;keys&#039;);
SELECT * FROM ft2 WHERE MATCH(copy) AGAINST(&#039;mykeyword&#039;);
copy
mykeyword Postg
mykeyword Postg
drop table ft2;
#######################################
#                                     #
#            Engine Aria              #
#                                     #
#######################################
set default_storage_engine=Aria;
create table t1 (old_c1 integer,
old_c2 integer,
c1 integer,
c2 integer,
c3 integer);
create view v1 as select * from t1 where c2=2;
create trigger trg_t1 before update on t1 for each row
begin
set new.old_c1=old.c1;
set new.old_c2=old.c2;
end;
/
insert into t1(c1,c2,c3)
values (1,1,1), (1,2,2), (1,3,3),
(2,1,4), (2,2,5), (2,3,6),
(2,4,7), (2,5,8);
insert into t1 select NULL, NULL, c1+10,c2,c3+10 from t1;
insert into t1 select NULL, NULL, c1+20,c2+1,c3+20 from t1;
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
create table tmp as select * from t1;
#######################################
#        Test without any index       #
#######################################
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
3	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#######################################
#          Test with an index         #
#######################################
create index t1_c2 on t1 (c2,c1);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	index	NULL	t1_c2	10	NULL	32	Using where; Using index; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	index	NULL	t1_c2	10	NULL	32	Using where; Using index; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	5	NULL	21	Using index condition
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	5	NULL	21	Using index condition
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	5	NULL	21	Using index condition
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	5	NULL	21	Using index condition
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	1	Using index
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ref	t1_c2	t1_c2	5	const	8	
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ref	t1_c2	t1_c2	5	const	8	Using where
2	DEPENDENT SUBQUERY	a	index	NULL	t1_c2	10	NULL	32	Using where; Using index
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	1	Using index condition
1	PRIMARY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	1	Using index; FirstMatch(t1)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	1	Using index condition; Using where
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,func	1	Using where; Using index
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	2	Using index condition
1	PRIMARY	t1	ref	t1_c2	t1_c2	5	const	8	Using index; FirstMatch(t1)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	2	Using index condition
3	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	5	const	8	Using where; Using index
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	1	Using index
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	10	test.t1.c2,test.t1.c1	1	Using index; FirstMatch(t1)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	10	test.t1.c2,test.t1.c1	1	Using index; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#######################################
#       Test with a primary key       #
#######################################
drop index t1_c2 on t1;
alter table t1 add primary key (c3);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	Using index
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	PRIMARY	PRIMARY	4	NULL	30	Using index condition; Using where
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
3	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	Using index
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	PRIMARY	4	NULL	2	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	index	NULL	PRIMARY	4	NULL	2	Using buffer
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	Using index
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
# Update with error &quot;Subquery returns more than 1 row&quot;
update t1 set c2=(select c2 from t1);
ERROR 21000: Subquery returns more than 1 row
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
# Update with error &quot;Subquery returns more than 1 row&quot;
# and order by
update t1 set c2=(select c2 from t1) order by c3;
ERROR 21000: Subquery returns more than 1 row
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
# Duplicate value on update a primary key
update t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
ERROR 23000: Duplicate entry &#039;0&#039; for key &#039;PRIMARY&#039;
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key with ignore
update ignore t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key and limit
update t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 limit 2;
ERROR 23000: Duplicate entry &#039;0&#039; for key &#039;PRIMARY&#039;
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key with ignore
# and limit
update ignore t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Update no rows found
update t1 set c1=10
where c1 &lt;2 and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1 + 10);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
10	1	1
10	2	2
10	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Update no rows changed
drop trigger trg_t1;
update t1 set c1=c1
where c1 &lt;2 and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 0
info: Rows matched: 3  Changed: 0  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
#
# Check call of after trigger
#
create or replace trigger trg_t2 after update on t1 for each row
begin
declare msg varchar(100);
if (new.c3 = 5) then
set msg=concat(&#039;in after update trigger on &#039;,new.c3);
SIGNAL SQLSTATE &#039;45000&#039; SET MESSAGE_TEXT = msg;
end if;
end;
/
update t1 set c1=2
where c3 in (select distinct a.c3 from t1 a where a.c1=t1.c1);
ERROR 45000: in after update trigger on 5
select c1,c2,c3 from t1;
c1	c2	c3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	1
2	1	4
2	2	2
2	2	5
2	3	3
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
#
# Check update with order by and after trigger
#
update t1 set c1=2
where c3 in (select distinct a.c3 from t1 a where a.c1=t1.c1)
order by t1.c2, t1.c1;
ERROR 45000: in after update trigger on 5
select c1,c2,c3 from t1;
c1	c2	c3
1	3	3
11	2	12
11	3	13
12	2	15
12	3	16
12	4	17
12	5	18
2	1	1
2	1	11
2	1	14
2	1	4
2	2	2
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
drop view v1;
#
# Check update on view with check option
#
create view v1 as select * from t1 where c2=2 with check option;
update v1 set c2=3 where c1=1;
ERROR 44000: CHECK OPTION failed `test`.`v1`
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
update v1 set c2=(select max(c3) from v1) where c1=1;
ERROR 44000: CHECK OPTION failed `test`.`v1`
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
update v1 set c2=(select min(va.c3) from v1 va), c1=0 where c1=1;
select c1,c2,c3 from t1;
c1	c2	c3
0	2	2
1	1	1
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
drop table tmp;
drop view v1;
drop table t1;
#
# Test on dynamic columns (blob)
#
create table assets (
item_name varchar(32) primary key, -- A common attribute for all items
dynamic_cols  blob  -- Dynamic columns will be stored here
);
INSERT INTO assets VALUES (&#039;MariaDB T-shirt&#039;,
COLUMN_CREATE(&#039;color&#039;, &#039;blue&#039;, &#039;size&#039;, &#039;XL&#039;));
INSERT INTO assets VALUES (&#039;Thinkpad Laptop&#039;,
COLUMN_CREATE(&#039;color&#039;, &#039;black&#039;, &#039;price&#039;, 500));
SELECT item_name, COLUMN_GET(dynamic_cols, &#039;color&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	blue
Thinkpad Laptop	black
UPDATE assets
SET dynamic_cols=COLUMN_ADD(dynamic_cols, &#039;warranty&#039;, &#039;3 years&#039;)
WHERE item_name=&#039;Thinkpad Laptop&#039;;
SELECT item_name,
COLUMN_GET(dynamic_cols, &#039;warranty&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	NULL
Thinkpad Laptop	3 years
UPDATE assets
SET dynamic_cols=COLUMN_ADD(dynamic_cols, &#039;warranty&#039;, &#039;4 years&#039;)
WHERE item_name in
(select b.item_name from assets b
where COLUMN_GET(b.dynamic_cols, &#039;color&#039; as char) =&#039;black&#039;);
SELECT item_name,
COLUMN_GET(dynamic_cols, &#039;warranty&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	NULL
Thinkpad Laptop	4 years
UPDATE assets SET dynamic_cols=COLUMN_ADD(dynamic_cols, &#039;warranty&#039;,
(select COLUMN_GET(b.dynamic_cols, &#039;color&#039; as char)
from assets b
where assets.item_name = item_name));
SELECT item_name,
COLUMN_GET(dynamic_cols, &#039;warranty&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	blue
Thinkpad Laptop	black
drop table assets;
#
# Test on fulltext columns
#
CREATE TABLE ft2(copy TEXT,FULLTEXT(copy));
INSERT INTO ft2(copy) VALUES
(&#039;MySQL vs MariaDB database&#039;),
(&#039;Oracle vs MariaDB database&#039;),
(&#039;PostgreSQL vs MariaDB database&#039;),
(&#039;MariaDB overview&#039;),
(&#039;Foreign keys&#039;),
(&#039;Primary keys&#039;),
(&#039;Indexes&#039;),
(&#039;Transactions&#039;),
(&#039;Triggers&#039;);
SELECT * FROM ft2 WHERE MATCH(copy) AGAINST(&#039;database&#039;);
copy
MySQL vs MariaDB database
Oracle vs MariaDB database
PostgreSQL vs MariaDB database
update ft2 set copy = (select max(concat(&#039;mykeyword &#039;,substr(b.copy,1,5)))
from ft2 b WHERE MATCH(b.copy) AGAINST(&#039;database&#039;))
where MATCH(copy) AGAINST(&#039;keys&#039;);
SELECT * FROM ft2 WHERE MATCH(copy) AGAINST(&#039;mykeyword&#039;);
copy
mykeyword Postg
mykeyword Postg
drop table ft2;
#######################################
#                                     #
#            Engine MyISAM            #
#                                     #
#######################################
set default_storage_engine=MyISAM;
create table t1 (old_c1 integer,
old_c2 integer,
c1 integer,
c2 integer,
c3 integer);
create view v1 as select * from t1 where c2=2;
create trigger trg_t1 before update on t1 for each row
begin
set new.old_c1=old.c1;
set new.old_c2=old.c2;
end;
/
insert into t1(c1,c2,c3)
values (1,1,1), (1,2,2), (1,3,3),
(2,1,4), (2,2,5), (2,3,6),
(2,4,7), (2,5,8);
insert into t1 select NULL, NULL, c1+10,c2,c3+10 from t1;
insert into t1 select NULL, NULL, c1+20,c2+1,c3+20 from t1;
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
create table tmp as select * from t1;
#######################################
#        Test without any index       #
#######################################
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
3	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#######################################
#          Test with an index         #
#######################################
create index t1_c2 on t1 (c2,c1);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	index	NULL	t1_c2	10	NULL	32	Using where; Using index; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	index	NULL	t1_c2	10	NULL	32	Using where; Using index; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	a	ref	t1_c2	t1_c2	5	test.t1.c2	5	Using index; FirstMatch(t1)
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	1	Using index
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ref	t1_c2	t1_c2	5	const	8	
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ref	t1_c2	t1_c2	5	const	8	Using where
2	DEPENDENT SUBQUERY	a	index	NULL	t1_c2	10	NULL	32	Using where; Using index
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	1	Using index condition
1	PRIMARY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	1	Using index; FirstMatch(t1)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	1	Using index condition; Using where
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,func	1	Using where; Using index
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	2	Using index condition
1	PRIMARY	t1	ref	t1_c2	t1_c2	5	const	8	Using index; FirstMatch(t1)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	range	t1_c2	t1_c2	10	NULL	2	Using index condition
3	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	5	const	8	Using where; Using index
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	1	Using index
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	10	test.t1.c2,test.t1.c1	1	Using index; FirstMatch(t1)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	10	test.t1.c2,test.t1.c1	1	Using index; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#######################################
#       Test with a primary key       #
#######################################
drop index t1_c2 on t1;
alter table t1 add primary key (c3);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	Using index
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	PRIMARY	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
3	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	Using index
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	OK
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	index	NULL	PRIMARY	4	NULL	2	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	index	NULL	PRIMARY	4	NULL	2	Using buffer
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	Using index
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
# Update with error &quot;Subquery returns more than 1 row&quot;
update t1 set c2=(select c2 from t1);
ERROR 21000: Subquery returns more than 1 row
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
# Update with error &quot;Subquery returns more than 1 row&quot;
# and order by
update t1 set c2=(select c2 from t1) order by c3;
ERROR 21000: Subquery returns more than 1 row
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
# Duplicate value on update a primary key
update t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
ERROR 23000: Duplicate entry &#039;0&#039; for key &#039;PRIMARY&#039;
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key with ignore
update ignore t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key and limit
update t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 limit 2;
ERROR 23000: Duplicate entry &#039;0&#039; for key &#039;PRIMARY&#039;
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key with ignore
# and limit
update ignore t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Update no rows found
update t1 set c1=10
where c1 &lt;2 and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1 + 10);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
10	1	1
10	2	2
10	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Update no rows changed
drop trigger trg_t1;
update t1 set c1=c1
where c1 &lt;2 and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 0
info: Rows matched: 3  Changed: 0  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
#
# Check call of after trigger
#
create or replace trigger trg_t2 after update on t1 for each row
begin
declare msg varchar(100);
if (new.c3 = 5) then
set msg=concat(&#039;in after update trigger on &#039;,new.c3);
SIGNAL SQLSTATE &#039;45000&#039; SET MESSAGE_TEXT = msg;
end if;
end;
/
update t1 set c1=2
where c3 in (select distinct a.c3 from t1 a where a.c1=t1.c1);
ERROR 45000: in after update trigger on 5
select c1,c2,c3 from t1;
c1	c2	c3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	1
2	1	4
2	2	2
2	2	5
2	3	3
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
#
# Check update with order by and after trigger
#
update t1 set c1=2
where c3 in (select distinct a.c3 from t1 a where a.c1=t1.c1)
order by t1.c2, t1.c1;
ERROR 45000: in after update trigger on 5
select c1,c2,c3 from t1;
c1	c2	c3
1	3	3
11	2	12
11	3	13
12	2	15
12	3	16
12	4	17
12	5	18
2	1	1
2	1	11
2	1	14
2	1	4
2	2	2
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
drop view v1;
#
# Check update on view with check option
#
create view v1 as select * from t1 where c2=2 with check option;
update v1 set c2=3 where c1=1;
ERROR 44000: CHECK OPTION failed `test`.`v1`
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
update v1 set c2=(select max(c3) from v1) where c1=1;
ERROR 44000: CHECK OPTION failed `test`.`v1`
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
update v1 set c2=(select min(va.c3) from v1 va), c1=0 where c1=1;
select c1,c2,c3 from t1;
c1	c2	c3
0	2	2
1	1	1
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
drop table tmp;
drop view v1;
drop table t1;
#
# Test on dynamic columns (blob)
#
create table assets (
item_name varchar(32) primary key, -- A common attribute for all items
dynamic_cols  blob  -- Dynamic columns will be stored here
);
INSERT INTO assets VALUES (&#039;MariaDB T-shirt&#039;,
COLUMN_CREATE(&#039;color&#039;, &#039;blue&#039;, &#039;size&#039;, &#039;XL&#039;));
INSERT INTO assets VALUES (&#039;Thinkpad Laptop&#039;,
COLUMN_CREATE(&#039;color&#039;, &#039;black&#039;, &#039;price&#039;, 500));
SELECT item_name, COLUMN_GET(dynamic_cols, &#039;color&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	blue
Thinkpad Laptop	black
UPDATE assets
SET dynamic_cols=COLUMN_ADD(dynamic_cols, &#039;warranty&#039;, &#039;3 years&#039;)
WHERE item_name=&#039;Thinkpad Laptop&#039;;
SELECT item_name,
COLUMN_GET(dynamic_cols, &#039;warranty&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	NULL
Thinkpad Laptop	3 years
UPDATE assets
SET dynamic_cols=COLUMN_ADD(dynamic_cols, &#039;warranty&#039;, &#039;4 years&#039;)
WHERE item_name in
(select b.item_name from assets b
where COLUMN_GET(b.dynamic_cols, &#039;color&#039; as char) =&#039;black&#039;);
SELECT item_name,
COLUMN_GET(dynamic_cols, &#039;warranty&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	NULL
Thinkpad Laptop	4 years
UPDATE assets SET dynamic_cols=COLUMN_ADD(dynamic_cols, &#039;warranty&#039;,
(select COLUMN_GET(b.dynamic_cols, &#039;color&#039; as char)
from assets b
where assets.item_name = item_name));
SELECT item_name,
COLUMN_GET(dynamic_cols, &#039;warranty&#039; as char) AS color
FROM assets;
item_name	color
MariaDB T-shirt	blue
Thinkpad Laptop	black
drop table assets;
#
# Test on fulltext columns
#
CREATE TABLE ft2(copy TEXT,FULLTEXT(copy));
INSERT INTO ft2(copy) VALUES
(&#039;MySQL vs MariaDB database&#039;),
(&#039;Oracle vs MariaDB database&#039;),
(&#039;PostgreSQL vs MariaDB database&#039;),
(&#039;MariaDB overview&#039;),
(&#039;Foreign keys&#039;),
(&#039;Primary keys&#039;),
(&#039;Indexes&#039;),
(&#039;Transactions&#039;),
(&#039;Triggers&#039;);
SELECT * FROM ft2 WHERE MATCH(copy) AGAINST(&#039;database&#039;);
copy
MySQL vs MariaDB database
Oracle vs MariaDB database
PostgreSQL vs MariaDB database
update ft2 set copy = (select max(concat(&#039;mykeyword &#039;,substr(b.copy,1,5)))
from ft2 b WHERE MATCH(b.copy) AGAINST(&#039;database&#039;))
where MATCH(copy) AGAINST(&#039;keys&#039;);
SELECT * FROM ft2 WHERE MATCH(copy) AGAINST(&#039;mykeyword&#039;);
copy
mykeyword Postg
mykeyword Postg
drop table ft2;
#######################################
#                                     #
#            Engine MEMORY            #
#                                     #
#######################################
set default_storage_engine=MEMORY;
create table t1 (old_c1 integer,
old_c2 integer,
c1 integer,
c2 integer,
c3 integer);
create view v1 as select * from t1 where c2=2;
create trigger trg_t1 before update on t1 for each row
begin
set new.old_c1=old.c1;
set new.old_c2=old.c2;
end;
/
insert into t1(c1,c2,c3)
values (1,1,1), (1,2,2), (1,3,3),
(2,1,4), (2,2,5), (2,3,6),
(2,4,7), (2,5,8);
insert into t1 select NULL, NULL, c1+10,c2,c3+10 from t1;
insert into t1 select NULL, NULL, c1+20,c2+1,c3+20 from t1;
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
create table tmp as select * from t1;
#######################################
#        Test without any index       #
#######################################
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
3	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#######################################
#          Test with an index         #
#######################################
create index t1_c2 on t1 (c2,c1);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	t1_c2	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	t1_c2	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	t1_c2	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	t1_c2	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	2	
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	2	FirstMatch(t1)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,func	2	Using where
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
3	DEPENDENT SUBQUERY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ref	t1_c2	t1_c2	10	const,test.t1.c1	2	
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	10	test.t1.c2,test.t1.c1	2	FirstMatch(t1)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	t1_c2	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ref	t1_c2	t1_c2	10	test.t1.c2,test.t1.c1	2	FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Operation failed
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#######################################
#       Test with a primary key       #
#######################################
drop index t1_c2 on t1;
alter table t1 add primary key (c3);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
#
# Update with value from subquery on the same table
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	
update t1 set c1=(select a.c3 from t1 a where a.c3 = t1.c3);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;5	5	*
2-&gt;6	6	*
2-&gt;7	7	*
2-&gt;8	8	*
11-&gt;11	11	 
11-&gt;12	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;15	15	*
12-&gt;16	16	*
12-&gt;17	17	*
12-&gt;18	18	*
21-&gt;21	21	 
21-&gt;22	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;25	25	*
22-&gt;26	26	*
22-&gt;27	27	*
22-&gt;28	28	*
31-&gt;31	31	 
31-&gt;32	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;35	35	*
32-&gt;36	36	*
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + possibly sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c1=10 where c1 &lt;2
and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;10	1	*
1-&gt;10	2	*
1-&gt;10	3	*
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with EXISTS subquery over the updated table
# in WHERE + non-sargable condition
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; Using filesort
1	PRIMARY	&lt;subquery2&gt;	eq_ref	distinct_key	distinct_key	4	func	1	
2	MATERIALIZED	a	ALL	NULL	NULL	NULL	NULL	32	
update t1 set c1=c1+10 where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 order by c2;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
1-&gt;11	3	*
NULL	4	 
NULL	5	 
2-&gt;12	6	*
2-&gt;12	7	*
2-&gt;12	8	*
NULL	11	 
NULL	12	 
11-&gt;21	13	*
NULL	14	 
NULL	15	 
12-&gt;22	16	*
12-&gt;22	17	*
12-&gt;22	18	*
NULL	21	 
21-&gt;31	22	*
21-&gt;31	23	*
NULL	24	 
22-&gt;32	25	*
22-&gt;32	26	*
22-&gt;32	27	*
22-&gt;32	28	*
NULL	31	 
31-&gt;41	32	*
31-&gt;41	33	*
NULL	34	 
32-&gt;42	35	*
32-&gt;42	36	*
32-&gt;42	37	*
32-&gt;42	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a reference to view in subquery
# in settable value
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update t1 set c1=c1 +(select max(a.c2) from v1 a
where a.c1 = t1.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;3	1	*
1-&gt;3	2	*
1-&gt;3	3	*
2-&gt;4	4	*
2-&gt;4	5	*
2-&gt;4	6	*
2-&gt;4	7	*
2-&gt;4	8	*
11-&gt;13	11	*
11-&gt;13	12	*
11-&gt;13	13	*
12-&gt;14	14	*
12-&gt;14	15	*
12-&gt;14	16	*
12-&gt;14	17	*
12-&gt;14	18	*
21-&gt;23	21	*
21-&gt;23	22	*
21-&gt;23	23	*
22-&gt;24	24	*
22-&gt;24	25	*
22-&gt;24	26	*
22-&gt;24	27	*
22-&gt;24	28	*
31-&gt;33	31	*
31-&gt;33	32	*
31-&gt;33	33	*
32-&gt;34	34	*
32-&gt;34	35	*
32-&gt;34	36	*
32-&gt;34	37	*
32-&gt;34	38	*
truncate table t1;
insert into t1 select * from tmp;
#
# Update view
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from v1;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
explain update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	PRIMARY	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	a	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + (select max(a.c2) from t1 a
where a.c1 = v1.c1) +10 where c3 &gt; 3;
affected rows: 7
info: Rows matched: 7  Changed: 7  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
2-&gt;17	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
11-&gt;24	12	*
NULL	13	 
NULL	14	 
12-&gt;27	15	*
NULL	16	 
NULL	17	 
NULL	18	 
21-&gt;35	21	*
NULL	22	 
NULL	23	 
22-&gt;38	24	*
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
31-&gt;45	31	*
NULL	32	 
NULL	33	 
32-&gt;48	34	*
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from v1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1 set c1=c1 + 1 where c1 &lt;2
and exists (select &#039;X&#039; from v1 a where a.c1 = v1.c1);
affected rows: 1
info: Rows matched: 1  Changed: 1  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update view with EXISTS and reference to the same view in subquery
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from v1 where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
3	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	32	Using where
update v1
set c1=(select max(a.c1)+10 from v1 a where a.c1 = v1.c1)
where c1 &lt;10 and exists (select &#039;X&#039; from v1 a where a.c2 = v1.c2);
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
1-&gt;11	2	*
NULL	3	 
NULL	4	 
2-&gt;12	5	*
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with IN predicand over the updated table in WHERE
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1); Using join buffer (flat, BNL join)
explain update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
1	PRIMARY	a	ALL	NULL	NULL	NULL	NULL	32	Using where; FirstMatch(t1)
update t1 set c3=c3+110 where c2 in (select distinct a.c2 from t1 a where t1.c1=a.c1);
affected rows: 32
info: Rows matched: 32  Changed: 32  Warnings: 0
select c3 from t1;
c3
111
112
113
114
115
116
117
118
121
122
123
124
125
126
127
128
131
132
133
134
135
136
137
138
141
142
143
144
145
146
147
148
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3) limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
1-&gt;1	1	 
1-&gt;2	2	*
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
NULL	37	 
NULL	38	 
truncate table t1;
insert into t1 select * from tmp;
#
# Update with a limit and an order by
#
analyze table t1 persistent for all;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	note	The storage engine for the table doesn&#039;t support analyze
explain select * from t1 order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
explain update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	32	Using filesort
2	DEPENDENT SUBQUERY	a	eq_ref	PRIMARY	PRIMARY	4	test.t1.c3	1	
update t1
set c1=(select a.c3 from t1 a where a.c3 = t1.c3)
order by c3 desc limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select concat(old_c1,&#039;-&gt;&#039;,c1),c3,
case when c1 != old_c1 then &#039;*&#039; else &#039; &#039; end &quot;Changed&quot; from t1;
concat(old_c1,&#039;-&gt;&#039;,c1)	c3	Changed
NULL	1	 
NULL	2	 
NULL	3	 
NULL	4	 
NULL	5	 
NULL	6	 
NULL	7	 
NULL	8	 
NULL	11	 
NULL	12	 
NULL	13	 
NULL	14	 
NULL	15	 
NULL	16	 
NULL	17	 
NULL	18	 
NULL	21	 
NULL	22	 
NULL	23	 
NULL	24	 
NULL	25	 
NULL	26	 
NULL	27	 
NULL	28	 
NULL	31	 
NULL	32	 
NULL	33	 
NULL	34	 
NULL	35	 
NULL	36	 
32-&gt;37	37	*
32-&gt;38	38	*
truncate table t1;
insert into t1 select * from tmp;
# Update with error &quot;Subquery returns more than 1 row&quot;
update t1 set c2=(select c2 from t1);
ERROR 21000: Subquery returns more than 1 row
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
# Update with error &quot;Subquery returns more than 1 row&quot;
# and order by
update t1 set c2=(select c2 from t1) order by c3;
ERROR 21000: Subquery returns more than 1 row
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
# Duplicate value on update a primary key
update t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
ERROR 23000: Duplicate entry &#039;0&#039; for key &#039;PRIMARY&#039;
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key with ignore
update ignore t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2) and c2 &gt;= 3;
affected rows: 20
info: Rows matched: 20  Changed: 20  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key and limit
update t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 limit 2;
ERROR 23000: Duplicate entry &#039;0&#039; for key &#039;PRIMARY&#039;
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Duplicate value on update a primary key with ignore
# and limit
update ignore t1 set c3=0
where exists (select &#039;X&#039; from t1 a where a.c2 = t1.c2)
and c2 &gt;= 3 limit 2;
affected rows: 2
info: Rows matched: 2  Changed: 2  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	0
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Update no rows found
update t1 set c1=10
where c1 &lt;2 and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1 + 10);
affected rows: 3
info: Rows matched: 3  Changed: 3  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
10	1	1
10	2	2
10	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
# Update no rows changed
drop trigger trg_t1;
update t1 set c1=c1
where c1 &lt;2 and exists (select &#039;X&#039; from t1 a where a.c1 = t1.c1);
affected rows: 0
info: Rows matched: 3  Changed: 0  Warnings: 0
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
#
# Check call of after trigger
#
create or replace trigger trg_t2 after update on t1 for each row
begin
declare msg varchar(100);
if (new.c3 = 5) then
set msg=concat(&#039;in after update trigger on &#039;,new.c3);
SIGNAL SQLSTATE &#039;45000&#039; SET MESSAGE_TEXT = msg;
end if;
end;
/
update t1 set c1=2
where c3 in (select distinct a.c3 from t1 a where a.c1=t1.c1);
ERROR 45000: in after update trigger on 5
select c1,c2,c3 from t1;
c1	c2	c3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	1
2	1	4
2	2	2
2	2	5
2	3	3
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
#
# Check update with order by and after trigger
#
update t1 set c1=2
where c3 in (select distinct a.c3 from t1 a where a.c1=t1.c1)
order by t1.c2, t1.c1;
ERROR 45000: in after update trigger on 5
select c1,c2,c3 from t1;
c1	c2	c3
1	3	3
11	2	12
11	3	13
12	2	15
12	3	16
12	4	17
12	5	18
2	1	1
2	1	11
2	1	14
2	1	4
2	2	2
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
drop view v1;
#
# Check update on view with check option
#
create view v1 as select * from t1 where c2=2 with check option;
update v1 set c2=3 where c1=1;
ERROR 44000: CHECK OPTION failed `test`.`v1`
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
update v1 set c2=(select max(c3) from v1) where c1=1;
ERROR 44000: CHECK OPTION failed `test`.`v1`
select c1,c2,c3 from t1;
c1	c2	c3
1	1	1
1	2	2
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
update v1 set c2=(select min(va.c3) from v1 va), c1=0 where c1=1;
select c1,c2,c3 from t1;
c1	c2	c3
0	2	2
1	1	1
1	3	3
11	1	11
11	2	12
11	3	13
12	1	14
12	2	15
12	3	16
12	4	17
12	5	18
2	1	4
2	2	5
2	3	6
2	4	7
2	5	8
21	2	21
21	3	22
21	4	23
22	2	24
22	3	25
22	4	26
22	5	27
22	6	28
31	2	31
31	3	32
31	4	33
32	2	34
32	3	35
32	4	36
32	5	37
32	6	38
truncate table t1;
insert into t1 select * from tmp;
drop table tmp;
drop view v1;
drop table t1;
set @@default_storage_engine=@save_default_engine;
#
# Test with MyISAM
#
create table t1 (old_c1 integer,
old_c2 integer,
c1 integer,
c2 integer,
c3 integer) engine=MyISAM;
insert t1 (c1,c2,c3) select 0,seq,seq%10 from seq_1_to_500;
insert t1 (c1,c2,c3) select 1,seq,seq%10 from seq_1_to_400;
insert t1 (c1,c2,c3) select 2,seq,seq%10 from seq_1_to_300;
insert t1 (c1,c2,c3) select 3,seq,seq%10 from seq_1_to_200;
create index t1_idx1 on t1(c3);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	Engine-independent statistics collected
test.t1	analyze	status	Table is already up to date
update t1 set c1=2 where exists (select &#039;x&#039; from t1);
select count(*) from t1 where c1=2;
count(*)
1400
update t1 set c1=3 where c3 in (select c3 from t1 b where t1.c3=b.c1);
select count(*) from t1 where c1=3;
count(*)
140
drop table t1;
#
# Test error on multi_update conversion on view
# with order by or limit
#
create table t1 (c1 integer) engine=InnoDb;
create table t2 (c1 integer) engine=InnoDb;
create view v1 as select t1.c1 as &quot;t1c1&quot; ,t2.c1 as &quot;t2c1&quot;
        from t1,t2 where t1.c1=t2.c1;
update v1 set t1c1=2 order by 1;
update v1 set t1c1=2 limit 1;
drop table t1;
drop table t2;
drop view v1;
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