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mysql查询时间戳和日期的转换

 

在数据库的使用中,经常需要按指定日期来查询记录,以便于统计,而在数据库中,有很多存储的是时间戳,

 

也有的直接存日期,查询的时候可能不是那么好弄.

 

mysql提供了两个函数:

 

          from_unixtime(time_stamp)   ->  将时间戳转换为日期

 

          unix_timestamp(date)             ->  将指定的日期或者日期字符串转换为时间戳

 

 

如:   from_unixtime(time_stamp)

 

[plain] select from_unixtime(1382544000);  +---------------------------+  | from_unixtime(1382544000) |  +---------------------------+  | 2013-10-24 00:00:00       |  +---------------------------+  如: unix_timestamp(date) [plain] select unix_timestamp(date(&#39;2013-10-24&#39;));  +------------------------------------+  | unix_timestamp(date(&#39;2013-10-24&#39;)) |  +------------------------------------+  |                         1382544000 |  +------------------------------------+  如果要查询当天的订单的记录:[plain] select count(*) from b_order Where  date_format(from_unixtime(create_time),&#39;%Y-%m-%d&#39;) = date_format(now(),&#39;%Y-%m-%d&#39;)  也可以这样:[plain] select count(*) from b_order Where  create_time >= unix_timestamp(&#39;2013-10-24 00:00:00&#39;) and create_time <=  unix_timestamp(&#39;2013-10-24 23:59:59&#39;) ;  

 


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