bug #15745 (COUNT(DISTINCT CONCAT(x,y)) returns wrong result

mysql-test/r/distinct.result:
  result added
mysql-test/t/distinct.test:
  testcase
sql/item_sum.cc:
  MYSQL_TYPE_VARCHAR can't be 'binary' compared even when it is
  binary

1 files changed, 24 insertions, 0 deletions

diff --git a/mysql-test/t/distinct.test b/mysql-test/t/distinct.test
index 6483284633f..45bd0c7a51c 100644
--- a/mysql-test/t/distinct.test
+++ b/mysql-test/t/distinct.test
@@ -358,3 +358,27 @@ select distinct id, IFNULL(dsc, '-') from t1;
 drop table t1;
 
 # End of 4.1 tests
+
+
+#
+# Bug #15745 ( COUNT(DISTINCT CONCAT(x,y)) returns wrong result)
+#
+CREATE TABLE t1 (
+  ID int(11) NOT NULL auto_increment,
+  x varchar(20) default NULL,
+  y decimal(10,0) default NULL,
+  PRIMARY KEY  (ID),
+  KEY (y)
+) ENGINE=MyISAM DEFAULT CHARSET=latin1;
+
+INSERT INTO t1 VALUES
+(1,'ba','-1'),
+(2,'ba','1150'),
+(306,'ba','-1'),
+(307,'ba','1150'),
+(611,'ba','-1'),
+(612,'ba','1150');
+
+select count(distinct x,y) from t1;
+select count(distinct concat(x,y)) from t1;
+drop table t1;