From 4acb33f67b64af0e875598eca60133d6801c5ba9 Mon Sep 17 00:00:00 2001
From: Tobias Reischmann <tobias.reischmann@wi.uni-muenster.de>
Date: Wed, 7 Jun 2017 12:43:22 +0200
Subject: [PATCH] MDL-59173 tablelib.php: changed default of $params in set_sql
 to array()

Default of $params = null leads to a problem in query_db().
There this value is used in array_merge, which can not handle null
values. If null is passed for one of the params the outcome will be null
independent of the value of the second param!
---
 lib/tablelib.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/tablelib.php b/lib/tablelib.php
index 84d077b5011..4dd84f8de56 100644
--- a/lib/tablelib.php
+++ b/lib/tablelib.php
@@ -1545,7 +1545,7 @@ class table_sql extends flexible_table {
      * Of course you can use sub-queries, JOINS etc. by putting them in the
      * appropriate clause of the query.
      */
-    function set_sql($fields, $from, $where, array $params = NULL) {
+    function set_sql($fields, $from, $where, array $params = array()) {
         $this->sql = new stdClass();
         $this->sql->fields = $fields;
         $this->sql->from = $from;