1 files changed, 8 insertions, 2 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index 36962a233b8..9fe69a3303f 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -6194,10 +6194,16 @@ return_zero_rows(JOIN *join, select_result *result,TABLE_LIST *tables,
   DBUG_RETURN(0);
 }
 
-
+/*
+  used only in JOIN::clear
+*/
 static void clear_tables(JOIN *join)
 {
-  for (uint i=0 ; i < join->tables ; i++)
+  /* 
+    must clear only the non-const tables, as const tables
+    are not re-calculated.
+  */
+  for (uint i=join->const_tables ; i < join->tables ; i++)
     mark_as_null_row(join->table[i]);		// All fields are NULL
 }