Utilize r34708 tweak. Various performance tweaks. For results in one non-main namespa...

diff --git a/includes/SpecialRecentchanges.php b/includes/SpecialRecentchanges.php
index fed7afd..1d2e108 100644 (file)
--- a/includes/SpecialRecentchanges.php
+++ b/includes/SpecialRecentchanges.php
@@ -159,22 +159,51 @@ function wfSpecialRecentchanges( $par, $specialPage ) {
                }
        }
 
-       # Namespace filtering
-       $hidem .= is_null( $namespace ) ?  '' : ' AND rc_namespace' . ($invert ? '!=' : '=') . $namespace;
-
-       // This is the big thing!
-
+       // JOIN on watchlist for users
        $uid = $wgUser->getID();
-
-       // Perform query
-       $forceclause = $dbr->useIndexClause("rc_timestamp");
-       $sql2 = "SELECT * FROM $recentchanges $forceclause".
-         ($uid ? "LEFT OUTER JOIN $watchlist ON wl_user={$uid} AND wl_title=rc_title AND wl_namespace=rc_namespace " : "") .
-         "WHERE rc_timestamp >= '{$cutoff}' {$hidem} " .
-         "ORDER BY rc_timestamp DESC";
-       $sql2 = $dbr->limitResult($sql2, $limit, 0);
-       $res = $dbr->query( $sql2, $fname );
-
+       if( $uid ) {
+               $tables = array( 'recentchanges', 'watchlist' );
+               $join_conds = array( 'watchlist' => array('LEFT JOIN',"wl_user={$uid} AND wl_title=rc_title AND wl_namespace=rc_namespace") );
+       } else {
+               $tables = array( 'recentchanges' );
+               $join_conds = array();
+       }
+       
+       # Namespace filtering
+       $hidem = is_null($namespace) ?  '' : ' AND rc_namespace' . ($invert ? '!=' : '=') . $namespace;
+       
+       // Is there either one namespace selected or excluded?
+       // Also, if this is the main namespace, just use timestamp index.
+       if( is_null($namespace) || $invert || $namespace == NS_MAIN ) {
+               $res = $dbr->select( $tables, '*',
+                       array( "rc_timestamp >= '{$cutoff}' {$hidem}" ),
+                       __METHOD__,
+                       array( 'ORDER BY' => 'rc_timestamp DESC', 'LIMIT' => $limit, 
+                               'USE INDEX' => array('recentchanges' => 'rc_timestamp') ),
+                       $join_conds );
+       // We have a new_namespace_time index! UNION over new=(0,1) and sort result set!
+       } else {
+               // New pages
+               $sqlNew = $dbr->selectSQLText( $tables, '*',
+                       array( 'rc_new' => 1,
+                               "rc_timestamp >= '{$cutoff}' {$hidem}" ),
+                       __METHOD__,
+                       array( 'ORDER BY' => 'rc_timestamp DESC', 'LIMIT' => $limit, 
+                               'USE INDEX' =>  array('recentchanges' => 'new_name_timestamp') ),
+                       $join_conds );
+               // Old pages
+               $sqlOld = $dbr->selectSQLText( $tables, '*',
+                       array( 'rc_new' => 0,
+                               "rc_timestamp >= '{$cutoff}' {$hidem}" ),
+                       __METHOD__,
+                       array( 'ORDER BY' => 'rc_timestamp DESC', 'LIMIT' => $limit, 
+                               'USE INDEX' =>  array('recentchanges' => 'new_name_timestamp') ),
+                       $join_conds );
+               # Join the two fast queries, and sort the result set
+               $sql = "($sqlNew) UNION ($sqlOld) ORDER BY rc_timestamp DESC LIMIT $limit";
+               $res = $dbr->query( $sql, __METHOD__ );
+       }
+       
        // Fetch results, prepare a batch link existence check query
        $rows = array();
        $batch = new LinkBatch;