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Bug #44290: explain crashes for subquery with distinct in

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SQL_SELECT::test_quick_select

The crash was caused by an incomplete cleanup of JOIN_TAB::select
during the filesort of rows for GROUP BY clause inside a subquery.
Queries where a quick index access is replaced with filesort was
was affected. For example:

  SELECT 1 FROM
    (SELECT COUNT(DISTINCT c1) FROM t1
       WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x

Quick index access related data in the SQL_SELECT::test_quick_select
function was inconsistent after an incomplete cleanup.
This function has been completed to prevent crashes in the
SQL_SELECT::test_quick_select function.
This commit is contained in:
Gleb Shchepa
2009-05-13 12:51:39 +05:00
parent 230f3f5208
commit fbb96b339a
3 changed files with 39 additions and 0 deletions
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19
mysql-test/include/mix1.inc
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@@ -1516,4 +1516,23 @@ DROP TABLE t1;
# DROP TABLE t1;
#
--echo #
--echo # Bug #44290: explain crashes for subquery with distinct in
--echo # SQL_SELECT::test_quick_select
--echo # (reproduced only with InnoDB tables)
--echo #
eval
CREATE TABLE t1 (c1 INT, c2 INT, c3 INT, KEY (c3), KEY (c2, c3))
ENGINE=$engine_type;
INSERT INTO t1 VALUES (1,1,1), (1,1,1), (1,1,2), (1,1,1), (1,1,2);
SELECT 1 FROM (SELECT COUNT(DISTINCT c1)
FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
EXPLAIN
SELECT 1 FROM (SELECT COUNT(DISTINCT c1)
FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
DROP TABLE t1;
--echo End of 5.1 tests