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Fix bug lp:827416

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Analysis:
Constant table optimization of the outer query finds that
the right side of the equality is a constant that can
be used for an eq_ref access to fetch one row from t1,
and substitute t1 with a constant. Thus constant optimization
triggers evaluation of the subquery during the optimize
phase of the outer query.

The innermost subquery requires a plan with a temporary
table because with InnoDB tables the exact count of rows
is not known, and the empty tables cannot be optimzied
way. JOIN::exec for the innermost subquery substitutes
the subquery tables with a temporary table.

When EXPLAIN gets to print the tables in the innermost
subquery, EXPLAIN needs to print the name of each table
through the corresponding TABLE_LIST object. However,
the temporary table created during execution doesn't
have a corresponding TABLE_LIST, so we get a null
pointer exception.

Solution:
The solution is to forbid using expensive constant
expressions for eq_ref access for contant table
optimization. Notice that eq_ref with a subquery
providing the value is still possible during regular
execution.
This commit is contained in:
unknown 2011-08-27 00:40:29 +03:00
parent ee28dec858
commit 2df1914791
12 changed files with 125 additions and 34 deletions
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2
mysql-test/r/group_min_max.result
View file

@ -2900,7 +2900,7 @@ NULL
EXPLAIN
SELECT MIN( a ) FROM t1 WHERE a = (SELECT a FROM t1 WHERE a < 0);
id select_type table type possible_keys key key_len ref rows Extra
x x x x x x x x x Impossible WHERE noticed after reading const tables
x x x x x x x x x Using where; Using index
x x x x x x x x x Using where; Using index
SELECT MIN( a ) FROM t1 WHERE a = (SELECT a FROM t1 WHERE a < 0);
MIN( a )

16
mysql-test/r/subselect.result
View file

@ -367,12 +367,12 @@ INSERT INTO t8 (pseudo,email) VALUES ('joce1','test1');
INSERT INTO t8 (pseudo,email) VALUES ('2joce1','2test1');
EXPLAIN EXTENDED SELECT pseudo,(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce')) FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using where; Using index
4 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index condition
3 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
Warnings:
Note 1003 select 'joce' AS `pseudo`,(select 'test' from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))
Note 1003 select `test`.`t8`.`pseudo` AS `pseudo`,(select `test`.`t8`.`email` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))
SELECT pseudo FROM t8 WHERE pseudo=(SELECT pseudo,email FROM
t8 WHERE pseudo='joce');
ERROR 21000: Operand should contain 1 column(s)
@ -543,6 +543,12 @@ SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=1) FROM (SELECT
numreponse (SELECT numeropost FROM t1 HAVING numreponse=1)
INSERT INTO t1 (numeropost,numreponse,pseudo) VALUES (1,1,'joce'),(1,2,'joce'),(1,3,'test');
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY t1 ref PRIMARY PRIMARY 3 const 2 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select 1 from `test`.`t1` where (`test`.`t1`.`numeropost` = 1))))
SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
ERROR 21000: Subquery returns more than 1 row
EXPLAIN EXTENDED SELECT MAX(numreponse) FROM t1 WHERE numeropost='1';
id select_type table type possible_keys key key_len ref rows filtered Extra
@ -551,10 +557,10 @@ Warnings:
Note 1003 select max(`test`.`t1`.`numreponse`) AS `MAX(numreponse)` from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`)
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT MAX(numreponse) FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using index
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
Warnings:
Note 1003 select 3 AS `numreponse` from `test`.`t1` where ((3 = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
drop table t1;
CREATE TABLE t1 (a int(1));
INSERT INTO t1 VALUES (1);

24
mysql-test/r/subselect_innodb.result
View file

@ -247,4 +247,28 @@ x
NULL
drop procedure p1;
drop tables t1,t2,t3;
#
# LP BUG#827416: Crash in select_describe() on EXPLAIN with DISTINCT in nested subqueries
#
CREATE TABLE t3 ( b int) ENGINE=InnoDB;
CREATE TABLE t2 ( c int) ENGINE=InnoDB;
CREATE TABLE t1 ( a int NOT NULL , PRIMARY KEY (a)) ENGINE=InnoDB;
EXPLAIN SELECT *
FROM t1
WHERE t1.a = (
SELECT SUM( c )
FROM t2
WHERE (SELECT DISTINCT b FROM t3) > 0);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 const PRIMARY PRIMARY 4 const 1 Using where; Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL 1
3 SUBQUERY t3 ALL NULL NULL NULL NULL 1 Using temporary
SELECT *
FROM t1
WHERE t1.a = (
SELECT SUM( c )
FROM t2
WHERE (SELECT DISTINCT b FROM t3) > 0);
a
DROP TABLE t1, t2, t3;
set optimizer_switch=@subselect_innodb_tmp;

16
mysql-test/r/subselect_no_mat.result
View file

@ -372,12 +372,12 @@ INSERT INTO t8 (pseudo,email) VALUES ('joce1','test1');
INSERT INTO t8 (pseudo,email) VALUES ('2joce1','2test1');
EXPLAIN EXTENDED SELECT pseudo,(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce')) FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using where; Using index
4 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index condition
3 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
Warnings:
Note 1003 select 'joce' AS `pseudo`,(select 'test' from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))
Note 1003 select `test`.`t8`.`pseudo` AS `pseudo`,(select `test`.`t8`.`email` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))
SELECT pseudo FROM t8 WHERE pseudo=(SELECT pseudo,email FROM
t8 WHERE pseudo='joce');
ERROR 21000: Operand should contain 1 column(s)
@ -548,6 +548,12 @@ SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=1) FROM (SELECT
numreponse (SELECT numeropost FROM t1 HAVING numreponse=1)
INSERT INTO t1 (numeropost,numreponse,pseudo) VALUES (1,1,'joce'),(1,2,'joce'),(1,3,'test');
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY t1 ref PRIMARY PRIMARY 3 const 2 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select 1 from `test`.`t1` where (`test`.`t1`.`numeropost` = 1))))
SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
ERROR 21000: Subquery returns more than 1 row
EXPLAIN EXTENDED SELECT MAX(numreponse) FROM t1 WHERE numeropost='1';
id select_type table type possible_keys key key_len ref rows filtered Extra
@ -556,10 +562,10 @@ Warnings:
Note 1003 select max(`test`.`t1`.`numreponse`) AS `MAX(numreponse)` from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`)
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT MAX(numreponse) FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using index
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
Warnings:
Note 1003 select 3 AS `numreponse` from `test`.`t1` where ((3 = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
drop table t1;
CREATE TABLE t1 (a int(1));
INSERT INTO t1 VALUES (1);

16
mysql-test/r/subselect_no_opts.result
View file

@ -368,12 +368,12 @@ INSERT INTO t8 (pseudo,email) VALUES ('joce1','test1');
INSERT INTO t8 (pseudo,email) VALUES ('2joce1','2test1');
EXPLAIN EXTENDED SELECT pseudo,(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce')) FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using where; Using index
4 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index condition
3 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
Warnings:
Note 1003 select 'joce' AS `pseudo`,(select 'test' from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))
Note 1003 select `test`.`t8`.`pseudo` AS `pseudo`,(select `test`.`t8`.`email` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))
SELECT pseudo FROM t8 WHERE pseudo=(SELECT pseudo,email FROM
t8 WHERE pseudo='joce');
ERROR 21000: Operand should contain 1 column(s)
@ -544,6 +544,12 @@ SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=1) FROM (SELECT
numreponse (SELECT numeropost FROM t1 HAVING numreponse=1)
INSERT INTO t1 (numeropost,numreponse,pseudo) VALUES (1,1,'joce'),(1,2,'joce'),(1,3,'test');
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY t1 ref PRIMARY PRIMARY 3 const 2 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select 1 from `test`.`t1` where (`test`.`t1`.`numeropost` = 1))))
SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
ERROR 21000: Subquery returns more than 1 row
EXPLAIN EXTENDED SELECT MAX(numreponse) FROM t1 WHERE numeropost='1';
id select_type table type possible_keys key key_len ref rows filtered Extra
@ -552,10 +558,10 @@ Warnings:
Note 1003 select max(`test`.`t1`.`numreponse`) AS `MAX(numreponse)` from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`)
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT MAX(numreponse) FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using index
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
Warnings:
Note 1003 select 3 AS `numreponse` from `test`.`t1` where ((3 = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
drop table t1;
CREATE TABLE t1 (a int(1));
INSERT INTO t1 VALUES (1);

16
mysql-test/r/subselect_no_semijoin.result
View file

@ -368,12 +368,12 @@ INSERT INTO t8 (pseudo,email) VALUES ('joce1','test1');
INSERT INTO t8 (pseudo,email) VALUES ('2joce1','2test1');
EXPLAIN EXTENDED SELECT pseudo,(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce')) FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using where; Using index
4 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index condition
3 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
Warnings:
Note 1003 select 'joce' AS `pseudo`,(select 'test' from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))
Note 1003 select `test`.`t8`.`pseudo` AS `pseudo`,(select `test`.`t8`.`email` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))
SELECT pseudo FROM t8 WHERE pseudo=(SELECT pseudo,email FROM
t8 WHERE pseudo='joce');
ERROR 21000: Operand should contain 1 column(s)
@ -544,6 +544,12 @@ SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=1) FROM (SELECT
numreponse (SELECT numeropost FROM t1 HAVING numreponse=1)
INSERT INTO t1 (numeropost,numreponse,pseudo) VALUES (1,1,'joce'),(1,2,'joce'),(1,3,'test');
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY t1 ref PRIMARY PRIMARY 3 const 2 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select 1 from `test`.`t1` where (`test`.`t1`.`numeropost` = 1))))
SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
ERROR 21000: Subquery returns more than 1 row
EXPLAIN EXTENDED SELECT MAX(numreponse) FROM t1 WHERE numeropost='1';
id select_type table type possible_keys key key_len ref rows filtered Extra
@ -552,10 +558,10 @@ Warnings:
Note 1003 select max(`test`.`t1`.`numreponse`) AS `MAX(numreponse)` from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`)
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT MAX(numreponse) FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using index
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
Warnings:
Note 1003 select 3 AS `numreponse` from `test`.`t1` where ((3 = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
drop table t1;
CREATE TABLE t1 (a int(1));
INSERT INTO t1 VALUES (1);

16
mysql-test/r/subselect_scache.result
View file

@ -371,12 +371,12 @@ INSERT INTO t8 (pseudo,email) VALUES ('joce1','test1');
INSERT INTO t8 (pseudo,email) VALUES ('2joce1','2test1');
EXPLAIN EXTENDED SELECT pseudo,(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce')) FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using where; Using index
4 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index condition
3 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
Warnings:
Note 1003 select 'joce' AS `pseudo`,(select 'test' from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))
Note 1003 select `test`.`t8`.`pseudo` AS `pseudo`,(select `test`.`t8`.`email` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))
SELECT pseudo FROM t8 WHERE pseudo=(SELECT pseudo,email FROM
t8 WHERE pseudo='joce');
ERROR 21000: Operand should contain 1 column(s)
@ -547,6 +547,12 @@ SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=1) FROM (SELECT
numreponse (SELECT numeropost FROM t1 HAVING numreponse=1)
INSERT INTO t1 (numeropost,numreponse,pseudo) VALUES (1,1,'joce'),(1,2,'joce'),(1,3,'test');
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY t1 ref PRIMARY PRIMARY 3 const 2 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select 1 from `test`.`t1` where (`test`.`t1`.`numeropost` = 1))))
SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
ERROR 21000: Subquery returns more than 1 row
EXPLAIN EXTENDED SELECT MAX(numreponse) FROM t1 WHERE numeropost='1';
id select_type table type possible_keys key key_len ref rows filtered Extra
@ -555,10 +561,10 @@ Warnings:
Note 1003 select max(`test`.`t1`.`numreponse`) AS `MAX(numreponse)` from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`)
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT MAX(numreponse) FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using index
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
Warnings:
Note 1003 select 3 AS `numreponse` from `test`.`t1` where ((3 = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
drop table t1;
CREATE TABLE t1 (a int(1));
INSERT INTO t1 VALUES (1);

16
mysql-test/suite/pbxt/r/subselect.result
View file

@ -362,12 +362,12 @@ INSERT INTO t8 (pseudo,email) VALUES ('joce1','test1');
INSERT INTO t8 (pseudo,email) VALUES ('2joce1','2test1');
EXPLAIN EXTENDED SELECT pseudo,(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce')) FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
1 PRIMARY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using where; Using index
4 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00
2 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using where
3 SUBQUERY t8 const PRIMARY PRIMARY 37 const 1 100.00 Using index
Warnings:
Note 1003 select 'joce' AS `pseudo`,(select 'test' from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where ('joce' = (select 'joce' from `test`.`t8` where 1))
Note 1003 select `test`.`t8`.`pseudo` AS `pseudo`,(select `test`.`t8`.`email` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))) AS `(SELECT email FROM t8 WHERE pseudo=(SELECT pseudo FROM t8 WHERE pseudo='joce'))` from `test`.`t8` where (`test`.`t8`.`pseudo` = (select 'joce' from `test`.`t8` where 1))
SELECT pseudo FROM t8 WHERE pseudo=(SELECT pseudo,email FROM
t8 WHERE pseudo='joce');
ERROR 21000: Operand should contain 1 column(s)
@ -535,6 +535,12 @@ SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=1) FROM (SELECT
numreponse (SELECT numeropost FROM t1 HAVING numreponse=1)
INSERT INTO t1 (numeropost,numreponse,pseudo) VALUES (1,1,'joce'),(1,2,'joce'),(1,3,'test');
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY t1 ref PRIMARY PRIMARY 3 const 2 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select 1 from `test`.`t1` where (`test`.`t1`.`numeropost` = 1))))
SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
ERROR 21000: Subquery returns more than 1 row
EXPLAIN EXTENDED SELECT MAX(numreponse) FROM t1 WHERE numeropost='1';
id select_type table type possible_keys key key_len ref rows filtered Extra
@ -543,10 +549,10 @@ Warnings:
Note 1003 select max(`test`.`t1`.`numreponse`) AS `MAX(numreponse)` from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`)
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT MAX(numreponse) FROM t1 WHERE numeropost='1');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using index
1 PRIMARY t1 const PRIMARY,numreponse PRIMARY 7 const,const 1 100.00 Using where; Using index
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Select tables optimized away
Warnings:
Note 1003 select 3 AS `numreponse` from `test`.`t1` where ((3 = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
Note 1003 select `test`.`t1`.`numreponse` AS `numreponse` from `test`.`t1` where ((`test`.`t1`.`numeropost` = 1) and (`test`.`t1`.`numreponse` = (select max(`test`.`t1`.`numreponse`) from `test`.`t1` where multiple equal(1, `test`.`t1`.`numeropost`))))
drop table t1;
CREATE TABLE t1 (a int(1));
INSERT INTO t1 VALUES (1);

3
mysql-test/suite/pbxt/t/subselect.test
View file

@ -278,8 +278,9 @@ SELECT (SELECT numeropost FROM t1 HAVING numreponse=a),numreponse FROM (SELECT *
SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=a) FROM (SELECT * FROM t1) as a;
SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=1) FROM (SELECT * FROM t1) as a;
INSERT INTO t1 (numeropost,numreponse,pseudo) VALUES (1,1,'joce'),(1,2,'joce'),(1,3,'test');
-- error 1242
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
-- error 1242
SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
EXPLAIN EXTENDED SELECT MAX(numreponse) FROM t1 WHERE numeropost='1';
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT MAX(numreponse) FROM t1 WHERE numeropost='1');
drop table t1;

3
mysql-test/t/subselect.test
View file

@ -292,8 +292,9 @@ SELECT (SELECT numeropost FROM t1 HAVING numreponse=a),numreponse FROM (SELECT *
SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=a) FROM (SELECT * FROM t1) as a;
SELECT numreponse, (SELECT numeropost FROM t1 HAVING numreponse=1) FROM (SELECT * FROM t1) as a;
INSERT INTO t1 (numeropost,numreponse,pseudo) VALUES (1,1,'joce'),(1,2,'joce'),(1,3,'test');
-- error ER_SUBQUERY_NO_1_ROW
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
-- error ER_SUBQUERY_NO_1_ROW
SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT 1 FROM t1 WHERE numeropost='1');
EXPLAIN EXTENDED SELECT MAX(numreponse) FROM t1 WHERE numeropost='1';
EXPLAIN EXTENDED SELECT numreponse FROM t1 WHERE numeropost='1' AND numreponse=(SELECT MAX(numreponse) FROM t1 WHERE numeropost='1');
drop table t1;

24
mysql-test/t/subselect_innodb.test
View file

@ -241,5 +241,27 @@ call p1();
drop procedure p1;
drop tables t1,t2,t3;
set optimizer_switch=@subselect_innodb_tmp;
--echo #
--echo # LP BUG#827416: Crash in select_describe() on EXPLAIN with DISTINCT in nested subqueries
--echo #
CREATE TABLE t3 ( b int) ENGINE=InnoDB;
CREATE TABLE t2 ( c int) ENGINE=InnoDB;
CREATE TABLE t1 ( a int NOT NULL , PRIMARY KEY (a)) ENGINE=InnoDB;
EXPLAIN SELECT *
FROM t1
WHERE t1.a = (
SELECT SUM( c )
FROM t2
WHERE (SELECT DISTINCT b FROM t3) > 0);
SELECT *
FROM t1
WHERE t1.a = (
SELECT SUM( c )
FROM t2
WHERE (SELECT DISTINCT b FROM t3) > 0);
DROP TABLE t1, t2, t3;
set optimizer_switch=@subselect_innodb_tmp;

7
sql/sql_select.cc
View file

@ -2993,6 +2993,7 @@ make_join_statistics(JOIN *join, List<TABLE_LIST> &tables_list,
uint i,table_count,const_count,key;
table_map found_const_table_map, all_table_map, found_ref, refs;
key_map const_ref, eq_part;
bool has_expensive_keyparts;
TABLE **table_vector;
JOIN_TAB *stat,*stat_end,*s,**stat_ref;
KEYUSE *keyuse,*start_keyuse;
@ -3314,12 +3315,17 @@ make_join_statistics(JOIN *join, List<TABLE_LIST> &tables_list,
refs=0;
const_ref.clear_all();
eq_part.clear_all();
has_expensive_keyparts= false;
do
{
if (keyuse->val->type() != Item::NULL_ITEM && !keyuse->optimize)
{
if (!((~found_const_table_map) & keyuse->used_tables))
{
const_ref.set_bit(keyuse->keypart);
if (keyuse->val->is_expensive())
has_expensive_keyparts= true;
}
else
refs|=keyuse->used_tables;
eq_part.set_bit(keyuse->keypart);
@ -3341,6 +3347,7 @@ make_join_statistics(JOIN *join, List<TABLE_LIST> &tables_list,
if (table->key_info[key].flags & HA_NOSAME)
{
if (const_ref == eq_part &&
!has_expensive_keyparts &&
!((outer_join & table->map) &&
(*s->on_expr_ref)->is_expensive()))
{ // Found everything for ref.