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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('2013-10-24')); +------------------------------------+ | unix_timestamp(date('2013-10-24')) | +------------------------------------+ | 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),'%Y-%m-%d') = date_format(now(),'%Y-%m-%d') 也可以这样:[plain] select count(*) from b_order Where create_time >= unix_timestamp('2013-10-24 00:00:00') and create_time <= unix_timestamp('2013-10-24 23:59:59') ;
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