diff --git a/mysql-test/include/diff_tables.inc b/mysql-test/include/diff_tables.inc
index 150c02d1d73..d6216f3fe1e 100644
--- a/mysql-test/include/diff_tables.inc
+++ b/mysql-test/include/diff_tables.inc
@@ -69,7 +69,7 @@ while ($_diff_i) {
 # and connect the appropriate server.
   let $_pos= `SELECT LOCATE(':', '$_diff_table')`;
   let $_diff_conn=`SELECT SUBSTR('$_diff_table', 1, $_pos-1)`;
-  if (`SELECT "XX$_diff_conn" <> "XX"`) {
+  if (`SELECT 'XX$_diff_conn' <> 'XX'`) {
     let $_diff_table=`SELECT SUBSTR('$_diff_table', $_pos+1)`;
     connection $_diff_conn;
   }