diff --git a/mysql-test/r/group_by.result b/mysql-test/r/group_by.result
index 3e082fa04e3..e279fca2a9d 100644
--- a/mysql-test/r/group_by.result
+++ b/mysql-test/r/group_by.result
@@ -722,3 +722,22 @@ WHERE hostname LIKE '%aol%'
     GROUP BY hostname;
 hostname	no
 cache-dtc-af05.proxy.aol.com	1
+DROP TABLE t1;
+CREATE TABLE t1 (a  int, b int);
+INSERT INTO t1 VALUES (1,2), (1,3);
+SELECT a, b FROM t1 GROUP BY 'const';
+a	b
+1	2
+SELECT DISTINCT a, b FROM t1 GROUP BY 'const';
+a	b
+1	2
+DROP TABLE t1;
+CREATE TABLE t1 (id INT, dt DATETIME);
+INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
+INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
+INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
+INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
+SELECT dt DIV 1 AS f, id FROM t1 GROUP BY f;
+f	id
+20050501123000	1
+DROP TABLE t1;
diff --git a/mysql-test/t/group_by.test b/mysql-test/t/group_by.test
index 21d5abcc287..382580cbd4e 100644
--- a/mysql-test/t/group_by.test
+++ b/mysql-test/t/group_by.test
@@ -1,3 +1,4 @@
+
 # Initialise
 --disable_warnings
 drop table if exists t1,t2,t3;
@@ -524,7 +525,7 @@ select min(b) from t1;
 drop table t1;
 
 #
-# Test for bug #11088: GROUP BY a BLOB colimn with COUNT(DISTINCT column1) 
+# Test for bug #11088: GROUP BY a BLOB column with COUNT(DISTINCT column1) 
 #
 
 CREATE TABLE t1 (id int PRIMARY KEY, user_id int, hostname longtext);
@@ -539,3 +540,28 @@ SELECT hostname, COUNT(DISTINCT user_id) as no FROM t1
   WHERE hostname LIKE '%aol%'
     GROUP BY hostname;
 
+DROP TABLE t1;
+
+#
+# Test for bug #8614: GROUP BY 'const' with DISTINCT  
+#
+
+CREATE TABLE t1 (a  int, b int);
+INSERT INTO t1 VALUES (1,2), (1,3);
+SELECT a, b FROM t1 GROUP BY 'const';
+SELECT DISTINCT a, b FROM t1 GROUP BY 'const';
+
+DROP TABLE t1;
+
+#
+# Test for bug #11385: GROUP BY for datetime converted to decimals  
+#
+
+CREATE TABLE t1 (id INT, dt DATETIME);
+INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
+INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
+INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
+INSERT INTO t1 VALUES ( 1, '2005-05-01 12:30:00' );
+SELECT dt DIV 1 AS f, id FROM t1 GROUP BY f;
+
+DROP TABLE t1;
diff --git a/sql/field.h b/sql/field.h
index 1d7669d540d..ba963418c7a 100644
--- a/sql/field.h
+++ b/sql/field.h
@@ -25,6 +25,7 @@
 #endif
 
 #define NOT_FIXED_DEC			31
+#define DATETIME_DEC                     6
 
 class Send_field;
 class Protocol;
@@ -861,6 +862,7 @@ public:
   enum ha_base_keytype key_type() const { return HA_KEYTYPE_ULONGLONG; }
 #endif
   enum Item_result cmp_type () const { return INT_RESULT; }
+  uint decimals() const { return DATETIME_DEC; }
   int  store(const char *to,uint length,CHARSET_INFO *charset);
   int  store(double nr);
   int  store(longlong nr);
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index afb221b03ba..5bafe1a7df4 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -678,9 +678,14 @@ JOIN::optimize()
       DBUG_RETURN(1);
   }
   simple_group= 0;
-  group_list= remove_const(this, group_list, conds,
-                           rollup.state == ROLLUP::STATE_NONE,
-                           &simple_group);
+  {
+    ORDER *old_group_list;
+    group_list= remove_const(this, (old_group_list= group_list), conds,
+                             rollup.state == ROLLUP::STATE_NONE,
+			     &simple_group);
+    if (old_group_list && !group_list)
+      select_distinct= 0;
+  }
   if (!group_list && group)
   {
     order=0;					// The output has only one row