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- Committer: Jay Pipes
- Date: 2009-01-30 05:54:48 UTC
- mto: (779.3.22 devel)
- mto: This revision was merged to the branch mainline in revision 823.
- Revision ID: jpipes@serialcoder-20090130055448-7hsp1jgrrl6wo2ki
Fixes crash in optimizer where LEFT JOIN was mixing with a subselect.
Problem was in the JOIN::flatten_subqueries() method, which was not
properly populating the join->cond member that was being passed to the
replace_where_subcondition() static function later on in the method call.
After checking out the source for MySQL 6.0, I noticed that the optimizer
team has punted on LEFT JOIN with dependent subqueries, probably because
of this issue, so I adapted the code from 6.0 into Drizzle.
After that, I modified the test case subselect_sj.test to put back in the
tests for LEFT JOIN on a condition with a subquery and verified that
the results returned were correct. The SELECT returns a valid and correct
data set now for both un-commented queries, and the EXPLAIN SELECT just
shows SUBQUERY, not DEPENDENT or UNIQUE SUBQUERY.
Problem was in the JOIN::flatten_subqueries() method, which was not
properly populating the join->cond member that was being passed to the
replace_where_subcondition() static function later on in the method call.
After checking out the source for MySQL 6.0, I noticed that the optimizer
team has punted on LEFT JOIN with dependent subqueries, probably because
of this issue, so I adapted the code from 6.0 into Drizzle.
After that, I modified the test case subselect_sj.test to put back in the
tests for LEFT JOIN on a condition with a subquery and verified that
the results returned were correct. The SELECT returns a valid and correct
data set now for both un-commented queries, and the EXPLAIN SELECT just
shows SUBQUERY, not DEPENDENT or UNIQUE SUBQUERY.
added
removed
drizzled/sql_select.cc
