diff options
Diffstat (limited to 'sql/opt_sum.cc')
-rw-r--r-- | sql/opt_sum.cc | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/sql/opt_sum.cc b/sql/opt_sum.cc index cefb507a61e..370fa9a6904 100644 --- a/sql/opt_sum.cc +++ b/sql/opt_sum.cc @@ -74,10 +74,12 @@ static int maxmin_in_range(bool max_fl, Field* field, COND *cond); # Multiplication of number of rows in all tables */ -static ulonglong get_exact_record_count(TABLE_LIST *tables) +static ulonglong get_exact_record_count(List<TABLE_LIST> &tables) { ulonglong count= 1; - for (TABLE_LIST *tl= tables; tl; tl= tl->next_leaf) + TABLE_LIST *tl; + List_iterator<TABLE_LIST> ti(tables); + while ((tl= ti++)) { ha_rows tmp= tl->table->file->records(); if ((tmp == HA_POS_ERROR)) @@ -110,9 +112,11 @@ static ulonglong get_exact_record_count(TABLE_LIST *tables) HA_ERR_... if a deadlock or a lock wait timeout happens, for example */ -int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) +int opt_sum_query(List<TABLE_LIST> &tables, List<Item> &all_fields,COND *conds) { List_iterator_fast<Item> it(all_fields); + List_iterator<TABLE_LIST> ti(tables); + TABLE_LIST *tl; int const_result= 1; bool recalc_const_item= 0; ulonglong count= 1; @@ -120,7 +124,7 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) table_map removed_tables= 0, outer_tables= 0, used_tables= 0; table_map where_tables= 0; Item *item; - int error; + int error= 0; if (conds) where_tables= conds->used_tables(); @@ -129,7 +133,7 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) Analyze outer join dependencies, and, if possible, compute the number of returned rows. */ - for (TABLE_LIST *tl= tables; tl; tl= tl->next_leaf) + while ((tl= ti++)) { TABLE_LIST *embedded; for (embedded= tl ; embedded; embedded= embedded->embedding) @@ -170,6 +174,14 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) is_exact_count= FALSE; count= 1; // ensure count != 0 } + else if (tl->is_materialized_derived()) + { + /* + Can't remove a derived table as it's number of rows is just an + estimate. + */ + return 0; + } else { error= tl->table->file->info(HA_STATUS_VARIABLE | HA_STATUS_NO_LOCK); |