mysql 统计按时和超时任务

SELECT
    SUM(CASE WHEN TIMESTAMPDIFF(SECOND,t1.advise_end_time, t1.finished_time) < 1 THEN 1 ELSE 0 END) AS 按时,
    SUM(CASE WHEN TIMESTAMPDIFF(SECOND,t1.advise_end_time, t1.finished_time) > 1 THEN 1 ELSE 0 END) AS 超时
FROM
    survey_task t1