如何将负时差值设置为零

Question

如果时差结果为负，我该如何设置为零

select TIMEDIFF('2016-01-29 12:28:18','2016-01-29 19:27:51') as diff;

| -06：59：33 |

Answer 1

试试这个：

select if((time_to_sec(TIMEDIFF('2016-01-29 12:28:18','2016-01-29 19:27:51'))/3600) < 0,0,TIMEDIFF('2016-01-29 12:28:18','2016-01-29 19:27:51')) as diff;