MySQL Timediff计数时间从晚上10点到早上6点

Question

SELECT 
     (time_to_sec(
      timediff('2011-01-26 23:51:20', 
        '2011-01-26 15:51:10') 
      ) /60 /60) 
    AS totalhours 

总小时数为8.我必须做什么，以便它只计算晚上10点到早上6点之间的小时数？

Answer 1

这绝对简单，如果你使用：

SELECT hour(timediff('2011-01-26 23:51:20', 
        '2011-01-26 15:51:10')) 
    AS totalhours 

Answer 2

使用timetosec，其他方法总是给你一个积极的结果...即

SELECT 
     (hour(
      timediff('2011-01-29 23:51:20', 
        '2011-01-26 15:51:10') 
      )) 
    AS totalhours 

=80 

SELECT 
     (hour(
      timediff('2011-01-26 23:51:20', 
        '2011-01-29 15:51:10') 
      )) 
    AS totalhours 

= 63