1 files changed, 25 insertions, 0 deletions
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index 65644b93331..c50321ebed7 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -1062,6 +1062,31 @@ void st_select_lex_node::exclude()
   */
 }
 
+void st_select_lex_unit::exclude_level()
+{
+  SELECT_LEX_UNIT *units= 0, **units_last= &units;
+  for(SELECT_LEX *sl= first_select(); sl; sl= sl->next_select())
+  {
+    if (sl->link_prev && (*sl->link_prev= sl->link_next))
+      sl->link_next->link_prev= sl->link_prev;
+    SELECT_LEX_UNIT **last= 0;
+    for (SELECT_LEX_UNIT *u= sl->first_inner_unit(); u; u= u->next_unit())
+      last= (SELECT_LEX_UNIT**)&(u->next);
+    if (last)
+    {
+      (*units_last)= sl->first_inner_unit();
+      units_last= last;
+    }
+  }
+  if (units)
+  {
+    (*prev)= units;
+    (*units_last)= (SELECT_LEX_UNIT*)next;
+  }
+  else
+    (*prev)= next;
+}
+
 st_select_lex* st_select_lex_node::select_lex()
 {
   DBUG_ENTER("st_select_lex_node::select_lex (never should be called)");