Commit 580f12cc authored by unknown's avatar unknown
Browse files

fixed error handling if creating derived table failed 

single row subquery always can return NULL (no rows found) (BUG#5590)


mysql-test/r/subselect.result:
  maybe_null flag returning by subquwery for temporary table creation
mysql-test/t/subselect.test:
  maybe_null flag returning by subquwery for temporary table creation
sql/item.cc:
  storing maybe_null in type holder
sql/item_subselect.cc:
  single row subquery always can return NULL (no rows found)
sql/sql_derived.cc:
  fixed error handling if creating derived table failed
parent f177c76f

mysql-test/r/subselect.result

+13 −2
Original line number Diff line number Diff line
@@ -1084,7 +1084,7 @@ SHOW CREATE TABLE t1; 
Table	Create Table

t1	CREATE TABLE `t1` (

  `a` bigint(20) NOT NULL default '0',

  `(SELECT a)` bigint(20) NOT NULL default '0'

  `(SELECT a)` bigint(20) default NULL

) ENGINE=MyISAM DEFAULT CHARSET=latin1

drop table t1;

CREATE TABLE t1 SELECT * FROM (SELECT 1 as a,(SELECT a+0)) a;
@@ -1102,7 +1102,7 @@ a 
SHOW CREATE TABLE t1;

Table	Create Table

t1	CREATE TABLE `t1` (

  `a` bigint(20) NOT NULL default '0'

  `a` bigint(20) default NULL

) ENGINE=MyISAM DEFAULT CHARSET=latin1

drop table t1;

create table t1 (a int);
@@ -1976,3 +1976,14 @@ create table t1 (x int); 
select  (select b.x from t1 as b where b.x=a.x) from t1 as a where a.x=2 group by a.x;

(select b.x from t1 as b where b.x=a.x)

drop table t1;

CREATE TABLE `t1` ( `master` int(10) unsigned NOT NULL default '0', `map` smallint(6) unsigned NOT NULL default '0', `slave` int(10) unsigned NOT NULL default '0', `access` int(10) unsigned NOT NULL default '0', UNIQUE KEY `access_u` (`master`,`map`,`slave`));

INSERT INTO `t1` VALUES (1,0,0,700),(1,1,1,400),(1,5,5,400),(1,12,12,400),(1,12,32,400),(4,12,32,400);

CREATE TABLE `t2` ( `id` int(10) unsigned NOT NULL default '0', `pid` int(10) unsigned NOT NULL default '0', `map` smallint(6) unsigned NOT NULL default '0', `level` tinyint(4) unsigned NOT NULL default '0', `title` varchar(255) default NULL, PRIMARY KEY  (`id`,`pid`,`map`), KEY `level` (`level`), KEY `id` (`id`,`map`)) ;

INSERT INTO `t2` VALUES (6,5,12,7,'a'),(12,0,0,7,'a'),(12,1,0,7,'a'),(12,5,5,7,'a'),(12,5,12,7,'a');

SELECT b.sc FROM (SELECT (SELECT a.access FROM t1 a WHERE a.map = op.map AND a.slave = op.pid AND a.master = 1) ac FROM t2 op WHERE op.id = 12 AND op.map = 0) b;

ERROR 42S22: Unknown column 'b.sc' in 'field list'

SELECT b.ac FROM (SELECT (SELECT a.access FROM t1 a WHERE a.map = op.map AND a.slave = op.pid AND a.master = 1) ac FROM t2 op WHERE op.id = 12 AND op.map = 0) b;

ac

700

NULL

drop tables t1,t2;

mysql-test/t/subselect.test

+13 −0
Original line number Diff line number Diff line
@@ -1270,3 +1270,16 @@ drop table t1; 
create table t1 (x int);

select  (select b.x from t1 as b where b.x=a.x) from t1 as a where a.x=2 group by a.x;

drop table t1;



#

# Test of correct maybe_null flag returning by subquwery for temporary table

# creation

#

CREATE TABLE `t1` ( `master` int(10) unsigned NOT NULL default '0', `map` smallint(6) unsigned NOT NULL default '0', `slave` int(10) unsigned NOT NULL default '0', `access` int(10) unsigned NOT NULL default '0', UNIQUE KEY `access_u` (`master`,`map`,`slave`));

INSERT INTO `t1` VALUES (1,0,0,700),(1,1,1,400),(1,5,5,400),(1,12,12,400),(1,12,32,400),(4,12,32,400);

CREATE TABLE `t2` ( `id` int(10) unsigned NOT NULL default '0', `pid` int(10) unsigned NOT NULL default '0', `map` smallint(6) unsigned NOT NULL default '0', `level` tinyint(4) unsigned NOT NULL default '0', `title` varchar(255) default NULL, PRIMARY KEY  (`id`,`pid`,`map`), KEY `level` (`level`), KEY `id` (`id`,`map`)) ;

INSERT INTO `t2` VALUES (6,5,12,7,'a'),(12,0,0,7,'a'),(12,1,0,7,'a'),(12,5,5,7,'a'),(12,5,12,7,'a');

-- error 1054

SELECT b.sc FROM (SELECT (SELECT a.access FROM t1 a WHERE a.map = op.map AND a.slave = op.pid AND a.master = 1) ac FROM t2 op WHERE op.id = 12 AND op.map = 0) b;

SELECT b.ac FROM (SELECT (SELECT a.access FROM t1 a WHERE a.map = op.map AND a.slave = op.pid AND a.master = 1) ac FROM t2 op WHERE op.id = 12 AND op.map = 0) b;

drop tables t1,t2;

sql/item.cc

+1 −0
Original line number Diff line number Diff line
@@ -2486,6 +2486,7 @@ Item_type_holder::Item_type_holder(THD *thd, Item *item) 
  else

    field_example= 0;

  max_length= real_length(item);

  maybe_null= item->maybe_null;

  collation.set(item->collation);

}

sql/item_subselect.cc

+0 −1
Original line number Diff line number Diff line
@@ -401,7 +401,6 @@ void Item_singlerow_subselect::fix_length_and_dec() 
    engine->fix_length_and_dec(row);

    value= *row;

  }

  maybe_null= engine->may_be_null();

}



uint Item_singlerow_subselect::cols()

sql/sql_derived.cc

+3 −0
Original line number Diff line number Diff line
@@ -224,7 +224,10 @@ static int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit, 
    }

  }

  else

  {

    free_tmp_table(thd, table);

    thd->lex->unit.cleanup();

  }



exit:

  delete derived_result;