diff options
| author | unknown <timour@askmonty.org> | 2011-11-09 16:46:08 +0200 |
|---|---|---|
| committer | unknown <timour@askmonty.org> | 2011-11-09 16:46:08 +0200 |
| commit | 30b396ad4c83a5f03084b4c999d43878fdbecff8 (patch) | |
| tree | a3dbff3db3f31af6087d3dac060977a649f582b2 /sql/opt_subselect.cc | |
| parent | 511459bd143262a9f154048d3bd87d8cb5239e52 (diff) | |
| download | mariadb-git-30b396ad4c83a5f03084b4c999d43878fdbecff8.tar.gz | |
- Removed a comment that is not true any more.
- Consistent use of the SUBS_NOT_TRANSFORMED constant for in_strategy.
Diffstat (limited to 'sql/opt_subselect.cc')
| -rw-r--r-- | sql/opt_subselect.cc | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/sql/opt_subselect.cc b/sql/opt_subselect.cc index aa0a8152bbb..f581f5601e4 100644 --- a/sql/opt_subselect.cc +++ b/sql/opt_subselect.cc @@ -411,7 +411,7 @@ int check_and_do_in_subquery_rewrites(JOIN *join) in_subs->emb_on_expr_nest && // 5 select_lex->outer_select()->join && // 6 parent_unit->first_select()->leaf_tables.elements && // 7 - !in_subs->in_strategy && // 8 + in_subs->in_strategy == SUBS_NOT_TRANSFORMED && // 8 select_lex->outer_select()->leaf_tables.elements && // 9 !((join->select_options | // 10 select_lex->outer_select()->join->select_options) // 10 @@ -479,7 +479,7 @@ int check_and_do_in_subquery_rewrites(JOIN *join) possible. */ if (optimizer_flag(thd, OPTIMIZER_SWITCH_IN_TO_EXISTS) || - !in_subs->in_strategy) + in_subs->in_strategy == SUBS_NOT_TRANSFORMED) { in_subs->in_strategy|= SUBS_IN_TO_EXISTS; } @@ -932,10 +932,6 @@ bool convert_join_subqueries_to_semijoins(JOIN *join) /* Revert to the IN->EXISTS strategy in the rare case when the subquery could not be flattened. - TODO: This is a limitation done for simplicity. Such subqueries could also - be executed via materialization. In order to determine this, we should - re-run the test for materialization that was done in - check_and_do_in_subquery_rewrites. */ in_subq->in_strategy= SUBS_IN_TO_EXISTS; if (is_materialization_applicable(thd, in_subq, @@ -4515,7 +4511,7 @@ bool JOIN::choose_subquery_plan(table_map join_tables) else return false; - DBUG_ASSERT(in_subs->in_strategy); /* A strategy must be chosen earlier. */ + DBUG_ASSERT(in_subs->in_strategy != SUBS_NOT_TRANSFORMED); /* A strategy must be chosen earlier. */ DBUG_ASSERT(in_to_exists_where || in_to_exists_having); DBUG_ASSERT(!in_to_exists_where || in_to_exists_where->fixed); DBUG_ASSERT(!in_to_exists_having || in_to_exists_having->fixed); |