diff options
Diffstat (limited to 'sql/opt_sum.cc')
| -rw-r--r-- | sql/opt_sum.cc | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/sql/opt_sum.cc b/sql/opt_sum.cc index 2ca6ddbab10..d8c61fa1a1d 100644 --- a/sql/opt_sum.cc +++ b/sql/opt_sum.cc @@ -245,8 +245,15 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds) const_result=0; } } - if (used_tables != removed_tables) - const_result=0; // We didn't remove all tables + /* + If we have a where clause, we can only ignore searching in the + tables if MIN/MAX optimisation replaced all used tables + This is to not to use replaced values in case of: + SELECT MIN(key) FROM table_1, empty_table + removed_tables is != 0 if we have used MIN() or MAX(). + */ + if (removed_tables && used_tables != removed_tables) + const_result= 0; // We didn't remove all tables return const_result; } |