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Merge from bk:ysql-next-mr-bugfixing.

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This commit is contained in:
Alexander Nozdrin 2010-01-06 13:11:57 +03:00
commit f471d82bb5
3 changed files with 104 additions and 0 deletions
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50
mysql-test/r/subselect3.result
View File

@ -964,3 +964,53 @@ Variable_name Value
Handler_read_rnd_next 18 Handler_read_rnd_next 18
DROP TABLE t1,t2; DROP TABLE t1,t2;
End of 5.1 tests End of 5.1 tests
#
# BUG#48920: COUNT DISTINCT returns 1 for NULL values when in a subquery
# in the select list
#
CREATE TABLE t1 (
i int(11) DEFAULT NULL,
v varchar(1) DEFAULT NULL
);
INSERT INTO t1 VALUES (8,'v');
INSERT INTO t1 VALUES (9,'r');
INSERT INTO t1 VALUES (NULL,'y');
CREATE TABLE t2 (
i int(11) DEFAULT NULL,
v varchar(1) DEFAULT NULL,
KEY i_key (i)
);
INSERT INTO t2 VALUES (NULL,'r');
INSERT INTO t2 VALUES (0,'c');
INSERT INTO t2 VALUES (0,'o');
INSERT INTO t2 VALUES (2,'v');
INSERT INTO t2 VALUES (7,'c');
SELECT i, v, (SELECT COUNT(DISTINCT i)
FROM t1
WHERE v = t2.v) as subsel
FROM t2;
i v subsel
NULL r 1
0 c 0
0 o 0
2 v 1
7 c 0
EXPLAIN EXTENDED
SELECT i, v, (SELECT COUNT(DISTINCT i)
FROM t1
WHERE v = t2.v) as subsel
FROM t2;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 5 100.00
2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1276 Field or reference 'test.t2.v' of SELECT #2 was resolved in SELECT #1
Note 1003 select `test`.`t2`.`i` AS `i`,`test`.`t2`.`v` AS `v`,(select count(distinct `test`.`t1`.`i`) AS `COUNT(DISTINCT i)` from `test`.`t1` where (`test`.`t1`.`v` = `test`.`t2`.`v`)) AS `subsel` from `test`.`t2`
DROP TABLE t1,t2;
End of 5.6 tests

47
mysql-test/t/subselect3.test
View File

@ -794,3 +794,50 @@ SHOW STATUS LIKE '%Handler_read_rnd_next';
DROP TABLE t1,t2; DROP TABLE t1,t2;
--echo End of 5.1 tests --echo End of 5.1 tests
--echo #
--echo # BUG#48920: COUNT DISTINCT returns 1 for NULL values when in a subquery
--echo # in the select list
--echo #
--echo
CREATE TABLE t1 (
i int(11) DEFAULT NULL,
v varchar(1) DEFAULT NULL
);
--echo
INSERT INTO t1 VALUES (8,'v');
INSERT INTO t1 VALUES (9,'r');
INSERT INTO t1 VALUES (NULL,'y');
--echo
CREATE TABLE t2 (
i int(11) DEFAULT NULL,
v varchar(1) DEFAULT NULL,
KEY i_key (i)
);
--echo
INSERT INTO t2 VALUES (NULL,'r');
INSERT INTO t2 VALUES (0,'c');
INSERT INTO t2 VALUES (0,'o');
INSERT INTO t2 VALUES (2,'v');
INSERT INTO t2 VALUES (7,'c');
--echo
SELECT i, v, (SELECT COUNT(DISTINCT i)
FROM t1
WHERE v = t2.v) as subsel
FROM t2;
--echo
EXPLAIN EXTENDED
SELECT i, v, (SELECT COUNT(DISTINCT i)
FROM t1
WHERE v = t2.v) as subsel
FROM t2;
DROP TABLE t1,t2;
--echo End of 5.6 tests

7
sql/item_sum.cc
View File

@ -578,7 +578,14 @@ int Item_sum::set_aggregator(Aggregator::Aggregator_type aggregator)
{ {
if (aggr) if (aggr)
{ {
/*
Dependent subselects may be executed multiple times, making
set_aggregator to be called multiple times. The aggregator type
will be the same, but it needs to be reset so that it is
reevaluated with the new dependent data.
*/
DBUG_ASSERT(aggregator == aggr->Aggrtype()); DBUG_ASSERT(aggregator == aggr->Aggrtype());
aggr->clear();
return FALSE; return FALSE;
} }
switch (aggregator) switch (aggregator)