support of simple row subselects (SCRUM)

mysql-test/r/subselect.result:
  test of simple row subselect
  fixed table droping
mysql-test/t/subselect.test:
  test of simple row subselect
  fixed table dropimg
sql/item.cc:
  Item_cache_str fixed to correctly store NULL and copy string value
sql/item.h:
  Item_cache_str fixed to correctly store NULL and copy string value
sql/item_cmpfunc.cc:
  support of simple row subselects
sql/item_subselect.cc:
  support of simple row subselects
sql/item_subselect.h:
  support of simple row subselects
sql/sql_class.cc:
  support of simple row subselects

2 files changed, 95 insertions, 2 deletions

diff --git a/mysql-test/r/subselect.result b/mysql-test/r/subselect.result
index 493768ece4a..d45b7b24585 100644
--- a/mysql-test/r/subselect.result
+++ b/mysql-test/r/subselect.result
@@ -52,6 +52,54 @@ a
 SELECT (SELECT 1) as a FROM (SELECT 1) b WHERE (SELECT a) IS NOT NULL;
 a
 1
+SELECT (SELECT 1,2,3) = ROW(1,2,3);
+(SELECT 1,2,3) = ROW(1,2,3)
+1
+SELECT (SELECT 1,2,3) = ROW(1,2,1);
+(SELECT 1,2,3) = ROW(1,2,1)
+0
+SELECT (SELECT 1,2,3) < ROW(1,2,1);
+(SELECT 1,2,3) < ROW(1,2,1)
+0
+SELECT (SELECT 1,2,3) > ROW(1,2,1);
+(SELECT 1,2,3) > ROW(1,2,1)
+1
+SELECT (SELECT 1,2,3) = ROW(1,2,NULL);
+(SELECT 1,2,3) = ROW(1,2,NULL)
+NULL
+SELECT ROW(1,2,3) = (SELECT 1,2,3);
+ROW(1,2,3) = (SELECT 1,2,3)
+1
+SELECT ROW(1,2,3) = (SELECT 1,2,1);
+ROW(1,2,3) = (SELECT 1,2,1)
+0
+SELECT ROW(1,2,3) < (SELECT 1,2,1);
+ROW(1,2,3) < (SELECT 1,2,1)
+0
+SELECT ROW(1,2,3) > (SELECT 1,2,1);
+ROW(1,2,3) > (SELECT 1,2,1)
+1
+SELECT ROW(1,2,3) = (SELECT 1,2,NULL);
+ROW(1,2,3) = (SELECT 1,2,NULL)
+NULL
+SELECT (SELECT 1.5,2,'a') = ROW(1.5,2,'a');
+(SELECT 1.5,2,'a') = ROW(1.5,2,'a')
+1
+SELECT (SELECT 1.5,2,'a') = ROW(1.5,2,'b');
+(SELECT 1.5,2,'a') = ROW(1.5,2,'b')
+0
+SELECT (SELECT 1.5,2,'a') = ROW('b',2,'b');
+(SELECT 1.5,2,'a') = ROW('b',2,'b')
+0
+SELECT (SELECT 'b',2,'a') = ROW(1.5,2,'a');
+(SELECT 'b',2,'a') = ROW(1.5,2,'a')
+0
+SELECT (SELECT 1.5,2,'a') = ROW(1.5,'c','a');
+(SELECT 1.5,2,'a') = ROW(1.5,'c','a')
+0
+SELECT (SELECT 1.5,'c','a') = ROW(1.5,2,'a');
+(SELECT 1.5,'c','a') = ROW(1.5,2,'a')
+0
 drop table if exists t1,t2,t3,t4,t5,t6,t7,t8;
 create table t1 (a int);
 create table t2 (a int, b int);
@@ -602,7 +650,7 @@ CREATE TABLE t1 (id int(11) default NULL, KEY id (id)) TYPE=MyISAM CHARSET=latin
 INSERT INTO t1 values (1),(1);
 UPDATE t SET id=(SELECT * FROM t1);
 Subselect returns more than 1 record
-drop table t;
+drop table t, t1;
 create table t (a int);
 insert into t values (1),(2),(3);
 select 1 IN (SELECT * from t);
@@ -705,3 +753,23 @@ select 10.5 > ANY (SELECT * from t);
 10.5 > ANY (SELECT * from t)
 1
 drop table t;
+create table t1 (a int, b int, c varchar(10));
+create table t2 (a int);
+insert into t1 values (1,2,'a'),(2,3,'b'),(3,4,'c');
+insert into t2 values (1),(2),(NULL);
+select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,2,'a'),(select c from t1 where a=t2.a)  from t2;
+a	(select a,b,c from t1 where t1.a=t2.a) = ROW(a,2,'a')	(select c from t1 where a=t2.a)
+1	1	a
+2	0	b
+NULL	NULL	NULL
+select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,3,'b'),(select c from t1 where a=t2.a) from t2;
+a	(select a,b,c from t1 where t1.a=t2.a) = ROW(a,3,'b')	(select c from t1 where a=t2.a)
+1	0	a
+2	1	b
+NULL	NULL	NULL
+select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,4,'c'),(select c from t1 where a=t2.a) from t2;
+a	(select a,b,c from t1 where t1.a=t2.a) = ROW(a,4,'c')	(select c from t1 where a=t2.a)
+1	0	a
+2	0	b
+NULL	NULL	NULL
+drop table t1,t2;
diff --git a/mysql-test/t/subselect.test b/mysql-test/t/subselect.test
index 0527d6a2001..ee3d31e66af 100644
--- a/mysql-test/t/subselect.test
+++ b/mysql-test/t/subselect.test
@@ -26,6 +26,22 @@ select (SELECT 1 FROM (SELECT 1) a PROCEDURE ANALYSE(1));
 SELECT 1 FROM (SELECT 1) a PROCEDURE ANALYSE((SELECT 1));
 SELECT (SELECT 1) as a FROM (SELECT 1) b WHERE (SELECT a) IS NULL;
 SELECT (SELECT 1) as a FROM (SELECT 1) b WHERE (SELECT a) IS NOT NULL;
+SELECT (SELECT 1,2,3) = ROW(1,2,3);
+SELECT (SELECT 1,2,3) = ROW(1,2,1);
+SELECT (SELECT 1,2,3) < ROW(1,2,1);
+SELECT (SELECT 1,2,3) > ROW(1,2,1);
+SELECT (SELECT 1,2,3) = ROW(1,2,NULL);
+SELECT ROW(1,2,3) = (SELECT 1,2,3);
+SELECT ROW(1,2,3) = (SELECT 1,2,1);
+SELECT ROW(1,2,3) < (SELECT 1,2,1);
+SELECT ROW(1,2,3) > (SELECT 1,2,1);
+SELECT ROW(1,2,3) = (SELECT 1,2,NULL);
+SELECT (SELECT 1.5,2,'a') = ROW(1.5,2,'a');
+SELECT (SELECT 1.5,2,'a') = ROW(1.5,2,'b');
+SELECT (SELECT 1.5,2,'a') = ROW('b',2,'b');
+SELECT (SELECT 'b',2,'a') = ROW(1.5,2,'a');
+SELECT (SELECT 1.5,2,'a') = ROW(1.5,'c','a');
+SELECT (SELECT 1.5,'c','a') = ROW(1.5,2,'a');
 
 drop table if exists t1,t2,t3,t4,t5,t6,t7,t8;
 create table t1 (a int);
@@ -363,7 +379,7 @@ CREATE TABLE t1 (id int(11) default NULL, KEY id (id)) TYPE=MyISAM CHARSET=latin
 INSERT INTO t1 values (1),(1);
 -- error 1240
 UPDATE t SET id=(SELECT * FROM t1);
-drop table t;
+drop table t, t1;
 
 
 #NULL test
@@ -409,3 +425,12 @@ select 10.5 > ALL (SELECT * from t);
 select 1.5 > ANY (SELECT * from t);
 select 10.5 > ANY (SELECT * from t);
 drop table t;
+
+create table t1 (a int, b int, c varchar(10));
+create table t2 (a int);
+insert into t1 values (1,2,'a'),(2,3,'b'),(3,4,'c');
+insert into t2 values (1),(2),(NULL);
+select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,2,'a'),(select c from t1 where a=t2.a)  from t2;
+select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,3,'b'),(select c from t1 where a=t2.a) from t2;
+select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,4,'c'),(select c from t1 where a=t2.a) from t2;
+drop table t1,t2;