X-Git-Url: http://git.cyclocoop.org/?a=blobdiff_plain;f=includes%2Fapi%2FApiQueryBacklinksprop.php;h=8e89c32e50d0c2798819ed0a2342906f9d54c57e;hb=76d62d7b204b48a0794032d2266ed64455058d13;hp=5b55332e1193bd1b3081fd4bb7288c05ae227fea;hpb=2e5a0882aaeec0376155d72a4bd7b3ff9c4b4eec;p=lhc%2Fweb%2Fwiklou.git

diff --git a/includes/api/ApiQueryBacklinksprop.php b/includes/api/ApiQueryBacklinksprop.php
index 5b55332e11..8e89c32e50 100644
--- a/includes/api/ApiQueryBacklinksprop.php
+++ b/includes/api/ApiQueryBacklinksprop.php
@@ -53,6 +53,7 @@ class ApiQueryBacklinksprop extends ApiQueryGeneratorBase {
 			'code' => 'lh',
 			'prefix' => 'pl',
 			'linktable' => 'pagelinks',
+			'indexes' => [ 'pl_namespace', 'pl_backlinks_namespace' ],
 			'from_namespace' => true,
 			'showredirects' => true,
 		],
@@ -60,6 +61,7 @@ class ApiQueryBacklinksprop extends ApiQueryGeneratorBase {
 			'code' => 'ti',
 			'prefix' => 'tl',
 			'linktable' => 'templatelinks',
+			'indexes' => [ 'tl_namespace', 'tl_backlinks_namespace' ],
 			'from_namespace' => true,
 			'showredirects' => true,
 		],
@@ -67,6 +69,7 @@ class ApiQueryBacklinksprop extends ApiQueryGeneratorBase {
 			'code' => 'fu',
 			'prefix' => 'il',
 			'linktable' => 'imagelinks',
+			'indexes' => [ 'il_to', 'il_backlinks_namespace' ],
 			'from_namespace' => true,
 			'to_namespace' => NS_FILE,
 			'exampletitle' => 'File:Example.jpg',
@@ -249,6 +252,24 @@ class ApiQueryBacklinksprop extends ApiQueryGeneratorBase {
 		// Override any ORDER BY from above with what we calculated earlier.
 		$this->addOption( 'ORDER BY', array_keys( $sortby ) );
 
+		// MySQL's optimizer chokes if we have too many values in "$bl_title IN
+		// (...)" and chooses the wrong index, so specify the correct index to
+		// use for the query. See T139056 for details.
+		if ( !empty( $settings['indexes'] ) ) {
+			list( $idxNoFromNS, $idxWithFromNS ) = $settings['indexes'];
+			if ( $params['namespace'] !== null && !empty( $settings['from_namespace'] ) ) {
+				$this->addOption( 'USE INDEX', [ $settings['linktable'] => $idxWithFromNS ] );
+			} else {
+				$this->addOption( 'USE INDEX', [ $settings['linktable'] => $idxNoFromNS ] );
+			}
+		}
+
+		// MySQL (or at least 5.5.5-10.0.23-MariaDB) chooses a really bad query
+		// plan if it thinks there will be more matching rows in the linktable
+		// than are in page. Use STRAIGHT_JOIN here to force it to use the
+		// intended, fast plan. See T145079 for details.
+		$this->addOption( 'STRAIGHT_JOIN' );
+
 		$this->addOption( 'LIMIT', $params['limit'] + 1 );
 
 		$res = $this->select( __METHOD__ );
@@ -313,7 +334,7 @@ class ApiQueryBacklinksprop extends ApiQueryGeneratorBase {
 		foreach ( $sortby as $field => $v ) {
 			$cont[] = $row->$field;
 		}
-		$this->setContinueEnumParameter( 'continue', join( '|', $cont ) );
+		$this->setContinueEnumParameter( 'continue', implode( '|', $cont ) );
 	}
 
 	public function getCacheMode( $params ) {