Commit 44662d2c authored by unknown's avatar unknown
Browse files

Merge epotemkin@bk-internal.mysql.com:/home/bk/mysql-4.1 

into moonbone.local:/work/14482-bug-4.1-mysql
parents ddf89750 3190b21f

mysql-test/r/select.result

+8 −0
Original line number Diff line number Diff line
@@ -2706,3 +2706,11 @@ select distinct count(f2) >0 from t1 left join t2 on f1=f3 group by f1; 
count(f2) >0

1

drop table t1,t2;

create table t1 (f1 int,f2 int);

insert into t1 values(1,1);

create table t2 (f3 int, f4 int, primary key(f3,f4));

insert into t2 values(1,1);

select * from t1 where f1 in (select f3 from t2 where (f3,f4)= (select f3,f4 from t2));

f1	f2

1	1

drop table t1,t2;

mysql-test/t/select.test

+11 −0
Original line number Diff line number Diff line
@@ -2237,4 +2237,15 @@ insert into t1 values (1,1); 
insert into t2 values (1,1),(1,2);

select distinct count(f2) >0 from t1 left join t2 on f1=f3 group by f1;

drop table t1,t2;



#

# Bug #14482 Server crash when subselecting from the same table

#

create table t1 (f1 int,f2 int);

insert into t1 values(1,1);

create table t2 (f3 int, f4 int, primary key(f3,f4));

insert into t2 values(1,1);

select * from t1 where f1 in (select f3 from t2 where (f3,f4)= (select f3,f4 from t2)); 

drop table t1,t2;



# End of 4.1 tests

sql/item.cc

+12 −3
Original line number Diff line number Diff line
@@ -2863,7 +2863,7 @@ Item_result item_cmp_type(Item_result a,Item_result b) 
void resolve_const_item(THD *thd, Item **ref, Item *comp_item)

{

  Item *item= *ref;

  Item *new_item;

  Item *new_item= NULL;

  if (item->basic_const_item())

    return;                                     // Can't be better

  Item_result res_type=item_cmp_type(comp_item->result_type(),
@@ -2892,8 +2892,17 @@ void resolve_const_item(THD *thd, Item **ref, Item *comp_item) 
    new_item= (null_value ? (Item*) new Item_null(name) :

               (Item*) new Item_int(name, result, length));

  }

  else if (res_type == ROW_RESULT)

  else if (res_type == ROW_RESULT && item->type() == Item::ROW_ITEM &&

           comp_item->type() == Item::ROW_ITEM)

  {

    /*

      Substitute constants only in Item_rows. Don't affect other Items

      with ROW_RESULT (eg Item_singlerow_subselect).



      For such Items more optimal is to detect if it is constant and replace

      it with Item_row. This would optimize queries like this:

      SELECT * FROM t1 WHERE (a,b) = (SELECT a,b FROM t2 LIMIT 1);

    */

    Item_row *item_row= (Item_row*) item;

    Item_row *comp_item_row= (Item_row*) comp_item;

    uint col;
@@ -2910,7 +2919,7 @@ void resolve_const_item(THD *thd, Item **ref, Item *comp_item) 
    while (col-- > 0)

      resolve_const_item(thd, item_row->addr(col), comp_item_row->el(col));

  }

  else

  else if (res_type == REAL_RESULT)

  {						// It must REAL_RESULT

    double result=item->val();

    uint length=item->max_length,decimals=item->decimals;