opt_sum.cc:

  Slightly improved the fix for bug #5406.

sql/opt_sum.cc

@@ -191,9 +191,8 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
 					   range_fl & NEAR_MIN ?
 					   HA_READ_AFTER_KEY :
 					   HA_READ_KEY_OR_NEXT);
-	  if ((!error || error == HA_ERR_KEY_NOT_FOUND) &&
-               reckey_in_range(0, &ref, item_field->field, 
-			       conds, range_fl, prefix_len))
+	  if (!error && reckey_in_range(0, &ref, item_field->field, 
+			                conds, range_fl, prefix_len))
 	    error= HA_ERR_KEY_NOT_FOUND;
           if (table->key_read)
           {
@@ -264,9 +263,8 @@ int opt_sum_query(TABLE_LIST *tables, List<Item> &all_fields,COND *conds)
 					   range_fl & NEAR_MAX ?
 					   HA_READ_BEFORE_KEY :
 					   HA_READ_PREFIX_LAST_OR_PREV);
-	  if ((!error || error == HA_ERR_KEY_NOT_FOUND) &&
-               reckey_in_range(1, &ref, item_field->field, 
-			       conds, range_fl, prefix_len))
+	  if (!error && reckey_in_range(1, &ref, item_field->field, 
+			                conds, range_fl, prefix_len))
 	    error= HA_ERR_KEY_NOT_FOUND;
           if (table->key_read)
           {