MDEV-9550 COUNT(NULL) returns incorrect result with sequence storage engine

when calculating COUNT(basic_const), take into account that
this basic_const may be NULL
This commit is contained in:
Sergei Golubchik 2016-02-22 12:52:29 +01:00
commit e6d51aac77
3 changed files with 18 additions and 3 deletions

View file

@ -452,7 +452,11 @@ int ha_seq_group_by_handler::next_row()
switch (item_sum->sum_func()) {
case Item_sum::COUNT_FUNC:
{
field->store((longlong) elements, 1);
Item *arg0= ((Item_sum*) item_sum)->get_arg(0);
if (arg0->basic_const_item() && arg0->is_null())
field->store(0LL, 1);
else
field->store((longlong) elements, 1);
break;
}
case Item_sum::SUM_FUNC: