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Fixed LP bug #889750.

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

View File

@ -190,13 +190,13 @@ pla_id test
explain SELECT STRAIGHT_JOIN d.pla_id, m2.mat_id FROM t1 m2 INNER JOIN (SELECT mp.pla_id, MIN(m1.matintnum) AS matintnum FROM t2 mp INNER JOIN t1 m1 ON mp.mat_id=m1.mat_id GROUP BY mp.pla_id) d ON d.matintnum=m2.matintnum;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY m2 ALL NULL NULL NULL NULL 9
1 PRIMARY <derived2> ALL NULL $hj 7 test.m2.matintnum 9 Using where
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 9 Using where
2 DERIVED mp ALL NULL NULL NULL NULL 9 Using temporary; Using filesort
2 DERIVED m1 eq_ref PRIMARY PRIMARY 3 test.mp.mat_id 1
explain SELECT STRAIGHT_JOIN d.pla_id, m2.test FROM t1 m2 INNER JOIN (SELECT mp.pla_id, MIN(m1.matintnum) AS matintnum FROM t2 mp INNER JOIN t1 m1 ON mp.mat_id=m1.mat_id GROUP BY mp.pla_id) d ON d.matintnum=m2.matintnum;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY m2 ALL NULL NULL NULL NULL 9
1 PRIMARY <derived2> ALL NULL $hj 7 test.m2.matintnum 9 Using where
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 9 Using where
2 DERIVED mp ALL NULL NULL NULL NULL 9 Using temporary; Using filesort
2 DERIVED m1 eq_ref PRIMARY PRIMARY 3 test.mp.mat_id 1
drop table t1,t2;