TIMEDIFF可以做now()-staytime > 5 minute

Question

一个 mysql的sql 需要删除 staytime字段（类型 时间）  与现在 时间 相差5分的记录now()-staytime > 5 minute我开始 选用的是TIMEDIFF  但是发现无法 应用  》5 分这个条件
例如
> SELECT TIMEDIFF('2000:01:01 00:00:00',    ->                 '2000:01:01 00:00:00.000001');        -> '-00:00:00.000001'
这里不知道哦啊如何表达 》 5分的条件后来我用
staytime< subdate(now, INTERVAL 5 MINUTE);
可以 完成 想知道TIMEDIFF可以做吗 ？ 或者还有其他方法？

Answer 1

mysql> SELECT TIMEDIFF('2010-10-10 10:10:00','2010-10-10 10:15:00');
+-------------------------------------------------------+
| TIMEDIFF('2010-10-10 10:10:00','2010-10-10 10:15:00') |
+-------------------------------------------------------+
| -00:05:00                                             |
+-------------------------------------------------------+
1 row in set (0.05 sec)mysql> SELECT TIMEDIFF('2010-10-10 10:20:00','2010-10-10 10:15:00');
+-------------------------------------------------------+
| TIMEDIFF('2010-10-10 10:20:00','2010-10-10 10:15:00') |
+-------------------------------------------------------+
| 00:05:00                                              |
+-------------------------------------------------------+
1 row in set (0.00 sec)mysql>

Answer 2

mysql> SELECT minute(TIMEDIFF('2010-10-10 10:20:00','2010-10-10 10:15:00'));
+---------------------------------------------------------------+
| minute(TIMEDIFF('2010-10-10 10:20:00','2010-10-10 10:15:00')) |
+---------------------------------------------------------------+
|                                                             5 |
+---------------------------------------------------------------+
1 row in set (0.00 sec)mysql>

Answer 3

where staytime<now()-interval 5 minute应该如上这样，这样的话，还可以使用staytime上的索引。

Answer 4

感谢楼上  where staytime<now()-interval 5 minute  这个按照道理是 最好