From: Domas Mituzas <midom@users.mediawiki.org>
Date: Tue, 8 May 2007 15:14:33 +0000 (+0000)
Subject: enforce join order for whatlinkshere queries - avoid filesorts at a cost of scanning... 
X-Git-Tag: 1.31.0-rc.0~53020
X-Git-Url: http://git.cyclocoop.org/fichier?a=commitdiff_plain;h=a52a3acd8bfcc25913cdcbf4bf4781dcd72b5aa7;p=lhc%2Fweb%2Fwiklou.git

enforce join order for whatlinkshere queries - avoid filesorts at a cost of scanning more records for damn namespace selector
---

diff --git a/includes/SpecialWhatlinkshere.php b/includes/SpecialWhatlinkshere.php
index d84326a8ca..a11e9d42c9 100644
--- a/includes/SpecialWhatlinkshere.php
+++ b/includes/SpecialWhatlinkshere.php
@@ -112,6 +112,11 @@ class WhatLinksHerePage {
 
 		// Read an extra row as an at-end check
 		$queryLimit = $limit + 1;
+		
+		// enforce join order, sometimes namespace selector may 
+		// trigger filesorts which are far less efficient than scanning many entries
+		$options[] = 'STRAIGHT_JOIN';
+		
 		$options['LIMIT'] = $queryLimit;
 		$fields = array( 'page_id', 'page_namespace', 'page_title', 'page_is_redirect' );