diff options
Diffstat (limited to 'sql/sql_select.cc')
| -rw-r--r-- | sql/sql_select.cc | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc index 1b676a72557..19e4be6f50d 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -7046,7 +7046,6 @@ void optimize_keyuse(JOIN *join, DYNAMIC_ARRAY *keyuse_array) } } - /** Check for the presence of AGGFN(DISTINCT a) queries that may be subject to loose index scan. @@ -7084,7 +7083,6 @@ is_indexed_agg_distinct(JOIN *join, List<Item_field> *out_args) { Item_sum **sum_item_ptr; bool result= false; - Field_map first_aggdistinct_fields; if (join->table_count != 1 || /* reference more than 1 table */ join->select_distinct || /* or a DISTINCT */ @@ -7094,10 +7092,11 @@ is_indexed_agg_distinct(JOIN *join, List<Item_field> *out_args) if (join->make_sum_func_list(join->all_fields, join->fields_list, true)) return false; + Bitmap<MAX_FIELDS> first_aggdistinct_fields; + bool first_aggdistinct_fields_initialized= false; for (sum_item_ptr= join->sum_funcs; *sum_item_ptr; sum_item_ptr++) { Item_sum *sum_item= *sum_item_ptr; - Field_map cur_aggdistinct_fields; Item *expr; /* aggregate is not AGGFN(DISTINCT) or more than 1 argument to it */ switch (sum_item->sum_func()) @@ -7120,6 +7119,8 @@ is_indexed_agg_distinct(JOIN *join, List<Item_field> *out_args) We don't worry about duplicates as these will be sorted out later in get_best_group_min_max */ + Bitmap<MAX_FIELDS> cur_aggdistinct_fields; + cur_aggdistinct_fields.clear_all(); for (uint i= 0; i < sum_item->get_arg_count(); i++) { expr= sum_item->get_arg(i); @@ -7138,8 +7139,11 @@ is_indexed_agg_distinct(JOIN *join, List<Item_field> *out_args) If there are multiple aggregate functions, make sure that they all refer to exactly the same set of columns. */ - if (first_aggdistinct_fields.is_clear_all()) - first_aggdistinct_fields.merge(cur_aggdistinct_fields); + if (!first_aggdistinct_fields_initialized) + { + first_aggdistinct_fields= cur_aggdistinct_fields; + first_aggdistinct_fields_initialized=true; + } else if (first_aggdistinct_fields != cur_aggdistinct_fields) return false; } |