From b84ed60fa9100f2bb5442004a0e9132ffbc40758 Mon Sep 17 00:00:00 2001
From: Andrew Nacin <nacin@git.wordpress.org>
Date: Wed, 26 Feb 2014 04:14:54 +0000
Subject: [PATCH] wpdb: set dbh to null when the mysqli connection fails. see
 #21663.

git-svn-id: https://develop.svn.wordpress.org/trunk@27277 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/wp-db.php | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/wp-includes/wp-db.php b/src/wp-includes/wp-db.php
index 667ee3b25a..4bba086d3f 100644
--- a/src/wp-includes/wp-db.php
+++ b/src/wp-includes/wp-db.php
@@ -1327,6 +1327,10 @@ class wpdb {
 			} else {
 				@mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
 			}
+
+			if ( $this->dbh->connect_errno ) {
+				$this->dbh = null;
+			}
 		} else {
 			if ( WP_DEBUG ) {
 				$this->dbh = mysql_connect( $this->dbhost, $this->dbuser, $this->dbpassword, $new_link, $client_flags );