--- mariadb-10.0.14/sql/sql_view.cc	2014-09-25 00:29:47.000000000 +0200
+++ mariadb-10.0.14-patched/sql/sql_view.cc	2014-10-30 12:30:17.344598704 +0100
@@ -159,31 +159,65 @@
 }
 
 
+
 /**
   Check if auto generated column names are conforming and
   possibly generate a conforming name for them if not.
 
-  @param item_list  List of Items which should be checked
-*/
+  @param  lex   LEX for this thread.
 
-static void make_valid_column_names(List<Item> &item_list)
+  @retval false Operation was a success.
+  @retval true  An error occurred.
+*/
+static bool make_valid_column_names(SELECT_LEX *select_lex)
 {
   Item *item;
-  uint name_len;
-  List_iterator_fast<Item> it(item_list);
+  size_t name_len;
   char buff[NAME_LEN];
+  uint column_no= 1;
   DBUG_ENTER("make_valid_column_names");
 
-  for (uint column_no= 1; (item= it++); column_no++)
+  for (SELECT_LEX *sl= select_lex; sl; sl= sl->next_select())
   {
-    if (!item->is_autogenerated_name || !check_column_name(item->name))
-      continue;
-    name_len= my_snprintf(buff, NAME_LEN, "Name_exp_%u", column_no);
-    item->orig_name= item->name;
-    item->set_name(buff, name_len, system_charset_info);
+    for (List_iterator_fast<Item> it(sl->item_list); (item= it++); column_no++)
+    {
+      if (!item->is_autogenerated_name || !check_column_name(item->name))
+        continue;
+      name_len= my_snprintf(buff, NAME_LEN, "Name_exp_%u", column_no);
+      item->orig_name= item->name;
+      item->set_name(buff, name_len, system_charset_info);
+    }
+
+    /*
+     There is a possibility of generating same name for column in more than
+     one SELECT_LEX. For Example:
+
+       CREATE TABLE t1 (Name_exp_1 INT, Name_exp_2 INT, Name_exp_3 INT);
+       CREATE TABLE t2 (Name_exp_1 INT, Name_exp_2 INT, Name_exp_3 INT);
+
+       CREATE VIEW v1 AS SELECT '', t1.Name_exp_2 AS Name_exp_2 FROM t1
+                         UNION
+                         SELECT '', t2.Name_exp_1 AS Name_exp_1 from t2;
+
+     But, column names of the first SELECT_LEX is considered
+     for the output.
+
+        mysql> SELECT * FROM v1;
+        +------------+------------+
+        | Name_exp_1 | Name_exp_2 |
+        +------------+------------+
+        |            |          2 |
+        |            |          3 |
+        +------------+------------+
+
+     So, checking for duplicate names in only "sl", current
+     SELECT_LEX.
+    */
+    if (check_duplicate_names(sl->item_list, 1))
+      DBUG_RETURN(true);
   }
 
-  DBUG_VOID_RETURN;
+  DBUG_RETURN(false);
 }
 
 
@@ -545,10 +579,7 @@
   }
 
   /* Check if the auto generated column names are conforming. */
-  for (sl= select_lex; sl; sl= sl->next_select())
-    make_valid_column_names(sl->item_list);
-
-  if (check_duplicate_names(select_lex->item_list, 1))
+  if (make_valid_column_names(select_lex))
   {
     res= TRUE;
     goto err;