r49821 MediaWiki - Code Review archive

maintenance/language/messages.inc was not updated.

Fixed in r49823.

Is this query going to get planned efficiently? It won't be able to use the type+action+page index.

I believe it will, yes ― I did consider that before committing the patch. I don't see any type+action+page index in the default schema. It will have been using page_time anyway, see lines 643 ff. in LogEventsList.php:

        if( $this->title || $this->pattern || $this->user ) {
            $index = array( 'USE INDEX' => array( 'logging' => array('page_time','user_time') ) );
        } else if( $this->type ) {
            $index = array( 'USE INDEX' => array( 'logging' => 'type_time' ) );
        } else {
            $index = array( 'USE INDEX' => array( 'logging' => 'times' ) );
        }

The first condition will get hit, since $this->title will be set, regardless of the action types. So it will retrieve by page, ordered by timestamp, and just filter out the ones with the wrong action. Adding more actions to include will make this marginally faster, if anything.

mysql> explain SELECT /* IndexPager::reallyDoQuery (LogPager) WikiSysop */  log_type,log_action,log_user,log_namespace,log_title,log_params,log_comment,log_id,log_deleted,log_timestamp,user_name,user_editcount,ts_tags  FROM `logging` FORCE INDEX (page_time,user_time) INNER JOIN `user` ON ((user_id=log_user)) LEFT JOIN `tag_summary` ON ((ts_log_id=log_id))  WHERE log_type IN ('move','delete')  AND log_namespace = '0' AND log_title = 'George_W._Bush' AND (user_id = log_user)  ORDER BY log_timestamp DESC LIMIT 51;
+-------------+--------+---------------------+-----------+---------+------------------+-------+-------------+
| table       | type   | possible_keys       | key       | key_len | ref              | rows  | Extra       |
+-------------+--------+---------------------+-----------+---------+------------------+-------+-------------+
| logging     | ref    | user_time,page_time | page_time |     259 | const,const      |   267 | Using where |
| user        | eq_ref | PRIMARY             | PRIMARY   |       4 | logging.log_user |     1 |             |
| tag_summary | ref    | ts_log_id           | ts_log_id |       5 | logging.log_id   | 18363 |             |
+-------------+--------+---------------------+-----------+---------+------------------+-------+-------------+

Yeah, looks like it's working fairly sensibly. Wikipedia:George W. Bush matches 41 of 51 log entries; worse cases should be relatively rare.