Merge mysql.com:/home/ram/work/mysql-4.1-maint

into  mysql.com:/home/ram/work/b27515/b27515.4.1

mysql-test/r/row.result

@@ -53,7 +53,7 @@ SELECT (1,2,3)=(1,NULL,3);
 NULL
 SELECT (1,2,3)=(1,NULL,0);
 (1,2,3)=(1,NULL,0)
-NULL
+0
 SELECT ROW(1,2,3)=ROW(1,2,3);
 ROW(1,2,3)=ROW(1,2,3)
 1
@@ -188,3 +188,100 @@ SELECT ROW(2,1) IN (ROW(21,2),ROW(ROW(1,1,3),0));
 ERROR 21000: Operand should contain 1 column(s)
 SELECT ROW(2,1) IN (ROW(ROW(1,1,3),0),ROW(21,2));
 ERROR 21000: Operand should contain 1 column(s)
+CREATE TABLE t1(a int, b int, c int);
+INSERT INTO t1 VALUES (1, 2, 3),
+(NULL, 2, 3  ), (1, NULL, 3  ), (1, 2,   NULL),
+(NULL, 2, 3+1), (1, NULL, 3+1), (1, 2+1, NULL),
+(NULL, 2, 3-1), (1, NULL, 3-1), (1, 2-1, NULL);
+SELECT (1,2,3) = (1,   NULL, 3);
+(1,2,3) = (1,   NULL, 3)
+NULL
+SELECT (1,2,3) = (1+1, NULL, 3);
+(1,2,3) = (1+1, NULL, 3)
+0
+SELECT (1,2,3) = (1,   NULL, 3+1);
+(1,2,3) = (1,   NULL, 3+1)
+0
+SELECT * FROM t1 WHERE (a,b,c) = (1,2,3);
+a	b	c
+1	2	3
+SELECT (1,2,3) <> (1,   NULL, 3);
+(1,2,3) <> (1,   NULL, 3)
+NULL
+SELECT (1,2,3) <> (1+1, NULL, 3);
+(1,2,3) <> (1+1, NULL, 3)
+1
+SELECT (1,2,3) <> (1,   NULL, 3+1);
+(1,2,3) <> (1,   NULL, 3+1)
+1
+SELECT * FROM t1 WHERE (a,b,c) <> (1,2,3);
+a	b	c
+NULL	2	4
+1	NULL	4
+1	3	NULL
+NULL	2	2
+1	NULL	2
+1	1	NULL
+SELECT (1,2,3) < (NULL, 2,    3);
+(1,2,3) < (NULL, 2,    3)
+NULL
+SELECT (1,2,3) < (1,    NULL, 3);
+(1,2,3) < (1,    NULL, 3)
+NULL
+SELECT (1,2,3) < (1-1,  NULL, 3);
+(1,2,3) < (1-1,  NULL, 3)
+0
+SELECT (1,2,3) < (1+1,  NULL, 3);
+(1,2,3) < (1+1,  NULL, 3)
+1
+SELECT * FROM t1 WHERE (a,b,c) < (1,2,3);
+a	b	c
+1	1	NULL
+SELECT (1,2,3) <= (NULL, 2,    3);
+(1,2,3) <= (NULL, 2,    3)
+NULL
+SELECT (1,2,3) <= (1,    NULL, 3);
+(1,2,3) <= (1,    NULL, 3)
+NULL
+SELECT (1,2,3) <= (1-1,  NULL, 3);
+(1,2,3) <= (1-1,  NULL, 3)
+0
+SELECT (1,2,3) <= (1+1,  NULL, 3);
+(1,2,3) <= (1+1,  NULL, 3)
+1
+SELECT * FROM t1 WHERE (a,b,c) <= (1,2,3);
+a	b	c
+1	2	3
+1	1	NULL
+SELECT (1,2,3) > (NULL, 2,    3);
+(1,2,3) > (NULL, 2,    3)
+NULL
+SELECT (1,2,3) > (1,    NULL, 3);
+(1,2,3) > (1,    NULL, 3)
+NULL
+SELECT (1,2,3) > (1-1,  NULL, 3);
+(1,2,3) > (1-1,  NULL, 3)
+1
+SELECT (1,2,3) > (1+1,  NULL, 3);
+(1,2,3) > (1+1,  NULL, 3)
+0
+SELECT * FROM t1 WHERE (a,b,c) > (1,2,3);
+a	b	c
+1	3	NULL
+SELECT (1,2,3) >= (NULL, 2,    3);
+(1,2,3) >= (NULL, 2,    3)
+NULL
+SELECT (1,2,3) >= (1,    NULL, 3);
+(1,2,3) >= (1,    NULL, 3)
+NULL
+SELECT (1,2,3) >= (1-1,  NULL, 3);
+(1,2,3) >= (1-1,  NULL, 3)
+1
+SELECT (1,2,3) >= (1+1,  NULL, 3);
+(1,2,3) >= (1+1,  NULL, 3)
+0
+SELECT * FROM t1 WHERE (a,b,c) >= (1,2,3);
+a	b	c
+1	2	3
+1	3	NULL
+DROP TABLE t1;

mysql-test/r/subselect.result

@@ -913,7 +913,7 @@ select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,2,'a'),(select c from t
 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
+NULL	0	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
@@ -923,7 +923,7 @@ select a, (select a,b,c from t1 where t1.a=t2.a) = ROW(a,4,'c'),(select c from t
 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
+NULL	0	NULL
 drop table t1,t2;
 create table t1 (a int, b real, c varchar(10));
 insert into t1 values (1, 1, 'a'), (2,2,'b'), (NULL, 2, 'b');

mysql-test/t/row.test

@@ -108,4 +108,49 @@ SELECT ROW(2,1) IN (ROW(21,2),ROW(ROW(1,1,3),0));
 --error 1241
 SELECT ROW(2,1) IN (ROW(ROW(1,1,3),0),ROW(21,2));
 
+#
+# Bug#27704: erroneous comparison of rows with NULL components
+#
+CREATE TABLE t1(a int, b int, c int);
+INSERT INTO t1 VALUES (1, 2, 3),
+  (NULL, 2, 3  ), (1, NULL, 3  ), (1, 2,   NULL),
+  (NULL, 2, 3+1), (1, NULL, 3+1), (1, 2+1, NULL),
+  (NULL, 2, 3-1), (1, NULL, 3-1), (1, 2-1, NULL);
+
+SELECT (1,2,3) = (1,   NULL, 3);
+SELECT (1,2,3) = (1+1, NULL, 3);
+SELECT (1,2,3) = (1,   NULL, 3+1);
+SELECT * FROM t1 WHERE (a,b,c) = (1,2,3);
+
+SELECT (1,2,3) <> (1,   NULL, 3);
+SELECT (1,2,3) <> (1+1, NULL, 3);
+SELECT (1,2,3) <> (1,   NULL, 3+1);
+SELECT * FROM t1 WHERE (a,b,c) <> (1,2,3);
+
+SELECT (1,2,3) < (NULL, 2,    3);
+SELECT (1,2,3) < (1,    NULL, 3);
+SELECT (1,2,3) < (1-1,  NULL, 3);
+SELECT (1,2,3) < (1+1,  NULL, 3);
+SELECT * FROM t1 WHERE (a,b,c) < (1,2,3);
+
+SELECT (1,2,3) <= (NULL, 2,    3);
+SELECT (1,2,3) <= (1,    NULL, 3);
+SELECT (1,2,3) <= (1-1,  NULL, 3);
+SELECT (1,2,3) <= (1+1,  NULL, 3);
+SELECT * FROM t1 WHERE (a,b,c) <= (1,2,3);
+
+SELECT (1,2,3) > (NULL, 2,    3);
+SELECT (1,2,3) > (1,    NULL, 3);
+SELECT (1,2,3) > (1-1,  NULL, 3);
+SELECT (1,2,3) > (1+1,  NULL, 3);
+SELECT * FROM t1 WHERE (a,b,c) > (1,2,3);
+
+SELECT (1,2,3) >= (NULL, 2,    3);
+SELECT (1,2,3) >= (1,    NULL, 3);
+SELECT (1,2,3) >= (1-1,  NULL, 3);
+SELECT (1,2,3) >= (1+1,  NULL, 3);
+SELECT * FROM t1 WHERE (a,b,c) >= (1,2,3);
+
+DROP TABLE t1;
+
 # End of 4.1 tests

sql/item_cmpfunc.cc

@@ -680,17 +680,45 @@ int Arg_comparator::compare_e_int_diff_signedness()
 int Arg_comparator::compare_row()
 {
   int res= 0;
+  bool was_null= 0;
   (*a)->bring_value();
   (*b)->bring_value();
   uint n= (*a)->cols();
   for (uint i= 0; i<n; i++)
   {
-    if ((res= comparators[i].compare()))
-      return res;
+    res= comparators[i].compare();
     if (owner->null_value)
-      return -1;
+    {
+      // NULL was compared
+      switch (owner->functype()) {
+      case Item_func::NE_FUNC:
+        break; // NE never aborts on NULL even if abort_on_null is set
+      case Item_func::LT_FUNC:
+      case Item_func::LE_FUNC:
+      case Item_func::GT_FUNC:
+      case Item_func::GE_FUNC:
+        return -1; // <, <=, > and >= always fail on NULL
+      default: // EQ_FUNC
+        if (owner->abort_on_null)
+          return -1; // We do not need correct NULL returning
       }
+      was_null= 1;
+      owner->null_value= 0;
+      res= 0;  // continue comparison (maybe we will meet explicit difference)
+    }
+    else if (res)
       return res;
+  }
+  if (was_null)
+  {
+    /*
+      There was NULL(s) in comparison in some parts, but there was no
+      explicit difference in other parts, so we have to return NULL.
+    */
+    owner->null_value= 1;
+    return -1;
+  }
+  return 0;
 }
 
 int Arg_comparator::compare_e_row()

sql/item_cmpfunc.h

@@ -206,10 +206,11 @@ class Item_bool_func2 :public Item_int_func
 protected:
   Arg_comparator cmp;
   String tmp_value1,tmp_value2;
+  bool abort_on_null;
 
 public:
   Item_bool_func2(Item *a,Item *b)
-    :Item_int_func(a,b), cmp(tmp_arg, tmp_arg+1) {}
+    :Item_int_func(a,b), cmp(tmp_arg, tmp_arg+1), abort_on_null(FALSE) {}
   void fix_length_and_dec();
   void set_cmp_func()
   {
@@ -222,6 +223,7 @@ class Item_bool_func2 :public Item_int_func
   bool is_null() { return test(args[0]->is_null() || args[1]->is_null()); }
   bool is_bool_func() { return 1; }
   CHARSET_INFO *compare_collation() { return cmp.cmp_collation.collation; }
+  void top_level_item() { abort_on_null= TRUE; }
 
   friend class  Arg_comparator;
 };