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Fixed LP bug #889750.

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If the optimizer switch 'semijoin_with_cache' is set to 'off' then 
join cache cannot be used to join inner tables of a semijoin.

Also fixed a bug in the function check_join_cache_usage() that led
to wrong output of the EXPLAIN commands for some test cases.
This commit is contained in:
Igor Babaev
2011-11-15 13:03:00 -08:00
parent db0aed9348
commit b4b7d941fe
30 changed files with 183 additions and 52 deletions
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4
mysql-test/r/explain.result
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@ -200,7 +200,7 @@ flush tables;
EXPLAIN SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN (SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.dt IS NULL );
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY OUTR ALL NULL NULL NULL NULL 2 Using where; Start temporary
1 PRIMARY INNR ALL NULL NULL NULL NULL 2 Using where; End temporary; Using join buffer (flat, BNL join)
1 PRIMARY INNR ALL NULL NULL NULL NULL 2 Using where; End temporary
flush tables;
SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN (SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.dt IS NULL );
dt
@ -208,7 +208,7 @@ flush tables;
EXPLAIN SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN ( SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.t < '2005-11-13 7:41:31' );
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY OUTR ALL NULL NULL NULL NULL 2 Using where; Start temporary
1 PRIMARY INNR ALL NULL NULL NULL NULL 2 Using where; End temporary; Using join buffer (flat, BNL join)
1 PRIMARY INNR ALL NULL NULL NULL NULL 2 Using where; End temporary
flush tables;
SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN ( SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.t < '2005-11-13 7:41:31' );
dt