Fix for bug #5555: "GROUP BY enum_field" returns incorrect results

mysql-test/r/func_group.result

@@ -693,3 +693,29 @@ SELECT MIN(a) FROM t1 WHERE a < 0;
 MIN(a)
 NULL
 DROP TABLE t1;
+CREATE TABLE t1 (
+id int(10) unsigned NOT NULL auto_increment,
+val enum('one','two','three') NOT NULL default 'one',
+PRIMARY KEY  (id)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8;
+INSERT INTO t1 VALUES
+(1,'one'),(2,'two'),(3,'three'),(4,'one'),(5,'two');
+select val, count(*) from t1 group by val;
+val	count(*)
+one	2
+two	2
+three	1
+drop table t1;
+CREATE TABLE t1 (
+id int(10) unsigned NOT NULL auto_increment,
+val set('one','two','three') NOT NULL default 'one',
+PRIMARY KEY  (id)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8;
+INSERT INTO t1 VALUES
+(1,'one'),(2,'two'),(3,'three'),(4,'one'),(5,'two');
+select val, count(*) from t1 group by val;
+val	count(*)
+one	2
+two	2
+three	1
+drop table t1;

mysql-test/t/func_group.test

@@ -431,6 +431,30 @@ SELECT MIN(a) FROM t1 WHERE a < 0;
 
 DROP TABLE t1;
 
+#
+# Bug #5555 GROUP BY enum_field" returns incorrect results
+#
  
+CREATE TABLE t1 (
+  id int(10) unsigned NOT NULL auto_increment,
+  val enum('one','two','three') NOT NULL default 'one',
+  PRIMARY KEY  (id)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8;
  
+INSERT INTO t1 VALUES
+(1,'one'),(2,'two'),(3,'three'),(4,'one'),(5,'two');
+ 
+select val, count(*) from t1 group by val;
+drop table t1;
 
+CREATE TABLE t1 (
+  id int(10) unsigned NOT NULL auto_increment,
+  val set('one','two','three') NOT NULL default 'one',
+  PRIMARY KEY  (id)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8;
+
+INSERT INTO t1 VALUES
+(1,'one'),(2,'two'),(3,'three'),(4,'one'),(5,'two');
+
+select val, count(*) from t1 group by val;
+drop table t1;

sql/ha_heap.cc

@@ -428,12 +428,8 @@ int ha_heap::create(const char *name, TABLE *table_arg,
 	seg->type= field->key_type();
       else
       {
-	if (!f_is_packed(flag) &&
-	    f_packtype(flag) == (int) FIELD_TYPE_DECIMAL &&
-	    !(field->charset() == &my_charset_bin))
-	  seg->type= (int) HA_KEYTYPE_TEXT;
-	else
-	  seg->type= (int) HA_KEYTYPE_BINARY;
+        if ((seg->type = field->key_type()) != (int) HA_KEYTYPE_TEXT)
+          seg->type= HA_KEYTYPE_BINARY;
       }
       seg->start=   (uint) key_part->offset;
       seg->length=  (uint) key_part->length;