DELETE `failed_builds` FROM `failed_builds` LEFT JOIN (SELECT `failed_builds`.`reason`,`failed_builds`.`build_assignment`, MAX(`failed_builds`.`date`) AS `max_date` FROM `failed_builds` GROUP BY CONCAT(`failed_builds`.`reason`,"-",`failed_builds`.`build_assignment`)) AS `last_log_q` ON `last_log_q`.`max_date`=`failed_builds`.`date` AND `last_log_q`.`reason`=`failed_builds`.`reason` AND `last_log_q`.`build_assignment`=`failed_builds`.`build_assignment` WHERE `last_log_q`.`reason` IS NULL;