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MWL#89: Cost-based choice between Materialization and IN->EXISTS transformation

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Fixes for multiple problems/bugs/test failures that resulted from moving
subquery optimization from the execution phase to the optimization phase.
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unknown
2010-09-05 18:43:47 +03:00
parent aa195b2570
commit 18ad3bdc2f
14 changed files with 528 additions and 269 deletions
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4
sql/sql_delete.cc
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@@ -92,6 +92,10 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds,
}
}
/* Apply the IN=>EXISTS transformation to all subqueries and optimize them. */
if (select_lex->optimize_unflattened_subqueries())
DBUG_RETURN(TRUE);
const_cond= (!conds || conds->const_item());
safe_update=test(thd->options & OPTION_SAFE_UPDATES);
if (safe_update && const_cond)