1 files changed, 28 insertions, 11 deletions

diff --git a/sql/sql_union.cc b/sql/sql_union.cc
index 6ab2619e8e2..41f4234c13d 100644
--- a/sql/sql_union.cc
+++ b/sql/sql_union.cc
@@ -68,7 +68,7 @@ void select_unit::change_select()
   curr_sel= current_select_number;
   /* New SELECT processing starts */
   DBUG_ASSERT(table->file->inited == 0);
-  step= thd->lex->current_select->linkage;
+  step= thd->lex->current_select->get_linkage();
   switch (step)
   {
   case INTERSECT_TYPE:
@@ -248,7 +248,7 @@ bool select_unit::send_eof()
 {
   if (step != INTERSECT_TYPE ||
       (thd->lex->current_select->next_select() &&
-       thd->lex->current_select->next_select()->linkage == INTERSECT_TYPE))
+       thd->lex->current_select->next_select()->get_linkage() == INTERSECT_TYPE))
   {
     /*
       it is not INTESECT or next SELECT in the sequence is INTERSECT so no
@@ -753,11 +753,11 @@ bool st_select_lex_unit::join_union_type_attributes(THD *thd_arg,
         been fixed yet. An Item_type_holder must be created based on a fixed
         Item, so use the inner Item instead.
       */
-      DBUG_ASSERT(item_tmp->fixed ||
+      DBUG_ASSERT(item_tmp->is_fixed() ||
                   (item_tmp->type() == Item::REF_ITEM &&
                    ((Item_ref *)(item_tmp))->ref_type() ==
                    Item_ref::OUTER_REF));
-      if (!item_tmp->fixed)
+      if (!item_tmp->is_fixed())
         item_tmp= item_tmp->real_item();
       holders[holder_pos].add_argument(item_tmp);
     }
@@ -982,7 +982,24 @@ bool st_select_lex_unit::prepare(TABLE_LIST *derived_arg,
     types= first_sl->item_list;
     goto cont;
   }
- 
+
+  if (sl->tvc && sl->order_list.elements &&
+      !sl->tvc->to_be_wrapped_as_with_tail())
+  {
+    if (thd->lex->context_analysis_only & CONTEXT_ANALYSIS_ONLY_VIEW)
+    {
+      sl->master_unit()->fake_select_lex= 0;
+      sl->master_unit()->saved_fake_select_lex= 0;
+    }
+    else
+    {
+      sl->order_list.empty();
+      sl->explicit_limit= 0;
+      sl->select_limit= 0;
+      sl->offset_limit= 0;
+    }
+  }
+
   for (;sl; sl= sl->next_select(), union_part_count++)
   {
     if (sl->tvc)
@@ -1102,12 +1119,12 @@ cont:
 
     while ((type= tp++))
     {
-      if (type->cmp_type() == STRING_RESULT &&
-          type->collation.derivation == DERIVATION_NONE)
-      {
-        my_error(ER_CANT_AGGREGATE_NCOLLATIONS, MYF(0), "UNION");
+      /*
+        Test if the aggregated data type is OK for a UNION element.
+        E.g. in case of string data, DERIVATION_NONE is not allowed.
+      */
+      if (type->type_handler()->union_element_finalize(type))
         goto err;
-      }
     }
     
     /*
@@ -1449,7 +1466,7 @@ bool st_select_lex_unit::exec()
         union_result->change_select();
       if (fake_select_lex)
       {
-        if (sl != &thd->lex->select_lex)
+        if (sl != thd->lex->first_select_lex())
           fake_select_lex->uncacheable|= sl->uncacheable;
         else
           fake_select_lex->uncacheable= 0;