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Fixed bug mdev-4366.

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When performing the range analysis for a conjunction the function
calculate_cond_selectivity_for_table should take in to account that
the analysis of some conjuncts may return SEL_ARG::IMPOSSIBLE.
This commit is contained in:
Igor Babaev
2013-04-04 14:11:31 -07:00
parent 50d4d1ca18
commit 4079a5dc3f
4 changed files with 102 additions and 11 deletions
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14
sql/opt_range.cc
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@ -3325,11 +3325,8 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item *cond)
table->cond_selectivity= 1.0;
#if 0
#else
if (table_records == 0)
DBUG_RETURN(FALSE);
#endif
if (thd->variables.optimizer_use_condition_selectivity > 2 &&
!bitmap_is_clear_all(used_fields))
@ -3338,6 +3335,7 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item *cond)
MEM_ROOT alloc;
SEL_TREE *tree;
SEL_ARG **key, **end;
double rows;
uint idx= 0;
init_sql_alloc(&alloc, thd->variables.range_alloc_block_size, 0,
@ -3364,12 +3362,18 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item *cond)
if (!tree)
goto free_alloc;
table->reginfo.impossible_range= 0;
if (tree->type == SEL_TREE::IMPOSSIBLE)
{
rows= 0;
table->reginfo.impossible_range= 1;
goto free_alloc;
}
for (key= tree->keys, end= key + param.keys; key != end; key++, idx++)
{
double rows;
if (*key)
{
table->reginfo.impossible_range= 0;
if ((*key)->type == SEL_ARG::IMPOSSIBLE)
{
rows= 0;