diff options
Diffstat (limited to 'sql/sql_select.h')
| -rw-r--r-- | sql/sql_select.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/sql/sql_select.h b/sql/sql_select.h index 4f9f6e9ed48..5be4f111bef 100644 --- a/sql/sql_select.h +++ b/sql/sql_select.h @@ -277,6 +277,14 @@ public: SELECT_LEX_UNIT *unit; // select that processed SELECT_LEX *select_lex; + /* + TRUE <=> optimizer must not mark any table as a constant table. + This is needed for subqueries in form "a IN (SELECT .. UNION SELECT ..): + when we optimize the select that reads the results of the union from a + temporary table, we must not mark the temp. table as constant because + the number of rows in it may vary from one subquery execution to another. + */ + bool no_const_tables; JOIN *tmp_join; // copy of this JOIN to be used with temporary tables ROLLUP rollup; // Used with rollup @@ -397,6 +405,8 @@ public: tmp_table_param.init(); tmp_table_param.end_write_records= HA_POS_ERROR; rollup.state= ROLLUP::STATE_NONE; + + no_const_tables= FALSE; } int prepare(Item ***rref_pointer_array, TABLE_LIST *tables, uint wind_num, |