From: Roan Kattouw <roan.kattouw@gmail.com>
Date: Tue, 28 Mar 2017 15:34:56 +0000 (-0400)
Subject: Make Title::getFirstRevision() ignore the rev_timestamp index
X-Git-Tag: 1.31.0-rc.0~3656^2~1
X-Git-Url: http://git.cyclocoop.org///%22%40url%40//%22?a=commitdiff_plain;h=dee457713b1b110bff1dc9985eabd487c5d8877c;p=lhc%2Fweb%2Fwiklou.git

Make Title::getFirstRevision() ignore the rev_timestamp index

We want the page_timestamp index to be used in this case, but sometimes
the rev_timestamp is chosen which leads to bad performance.

Also update WikiPage::getOldestRevision() which uses the exact same query.
I'll implement one in terms of the other in a follow-up commit.

Bug: T159319
Change-Id: I7c5c0a9b1af99ce2b5f4bdcc99710d8400ca8bcf
---

diff --git a/includes/Title.php b/includes/Title.php
index e45994c094..0c5835ca42 100644
--- a/includes/Title.php
+++ b/includes/Title.php
@@ -4028,7 +4028,11 @@ class Title implements LinkTarget {
 			$row = $db->selectRow( 'revision', Revision::selectFields(),
 				[ 'rev_page' => $pageId ],
 				__METHOD__,
-				[ 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 1 ]
+				[
+					'ORDER BY' => 'rev_timestamp ASC',
+					'LIMIT' => 1,
+					'IGNORE INDEX' => 'rev_timestamp'
+				]
 			);
 			if ( $row ) {
 				return new Revision( $row );
diff --git a/includes/page/WikiPage.php b/includes/page/WikiPage.php
index 4bc8ad6125..1d5973b809 100644
--- a/includes/page/WikiPage.php
+++ b/includes/page/WikiPage.php
@@ -590,7 +590,8 @@ class WikiPage implements Page, IDBAccessObject {
 				],
 				__METHOD__,
 				[
-					'ORDER BY' => 'rev_timestamp ASC'
+					'ORDER BY' => 'rev_timestamp ASC',
+					'IGNORE INDEX' => 'rev_timestamp'
 				]
 			);