请教一个查询语句写法

Question

请问一下，mysql中怎么 判断2个datetime日期相隔的小时数，如2009-05-04 10:50:30 与2009-05-05 14:30:30,得到的值应该是 28

Answer 1

select hour(timediff('2009-05-04 10:50:30','2009-05-05 14:30:30'))+1

Answer 2

mysql> select TIMEDIFF('2009-05-04 10:50:30','2009-05-05 14:30:30');
+-------------------------------------------------------+
| TIMEDIFF('2009-05-04 10:50:30','2009-05-05 14:30:30') |
+-------------------------------------------------------+
| -27:40:00                                             |
+-------------------------------------------------------+
1 row in set (0.08 sec)mysql>