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Set new default values for the optimizer switch flags 'derived_merge'

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and 'derived_with_keys'. Now they are set on by default.
This commit is contained in:
Igor Babaev
2011-11-26 14:23:00 -08:00
parent d84ea521c5
commit 17b4e4a194
49 changed files with 208 additions and 21 deletions
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3
mysql-test/r/explain.result
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@ -309,6 +309,8 @@ End of 5.1 tests.
CREATE TABLE t1 (a int) ;
CREATE TABLE t2 (a int) ;
INSERT INTO t2 VALUES (8);
set @tmp_optimizer_switch=@@optimizer_switch;
set optimizer_switch='derived_merge=off,derived_with_keys=off';
EXPLAIN EXTENDED
SELECT * FROM ( SELECT t1.a FROM t1,t2 WHERE t2.a = t1.a ) AS t;
id select_type table type possible_keys key key_len ref rows filtered Extra
@ -316,4 +318,5 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
2 DERIVED NULL NULL NULL NULL NULL NULL NULL NULL no matching row in const table
Warnings:
Note 1003 select NULL AS `a` from (select NULL AS `a` from `test`.`t1` join `test`.`t2` where 0) `t`
set optimizer_switch=@tmp_optimizer_switch;
DROP TABLE t1,t2;