1 files changed, 6 insertions, 0 deletions
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index c028d49d620..491ed37e63a 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -4590,6 +4590,12 @@ bool st_select_lex::is_merged_child_of(st_select_lex *ancestor)
     {
       continue;
     }
+
+    if (sl->master_unit()->derived &&
+      sl->master_unit()->derived->is_merged_derived())
+    {
+      continue;
+    }
     all_merged= FALSE;
     break;
   }