mysql 分級構建排序語句

1.使用case when  

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ORDER BY CASE WHEN end_time>NOW() AND start_time < NOW() THEN 0 WHEN start_time > NOW() THEN 1 ELSE 2 END,ABS(TIMESTAMPDIFF(second,start_time,NOW()))

2.使用 if

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ORDER BY IF(end_time>NOW(),0,1),ABS(TIMESTAMPDIFF(SECOND,start_time,NOW()))