Oracle中查询同一个日期字段，格式不同的问题-Mysql Tutorial-php.cn

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Oracle中查询同一个日期字段，格式不同的问题

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Jun 07, 2016 pm 05:06 PM

oracle database

数据库中某日期字段有如下数据，sql语句如下： select age, money, birthday from userinfo 仔细观察，日期字段有两种格式

数据库中某日期字段有如下数据，sql语句如下：

select age, money, birthday from userinfo

仔细观察，，日期字段有两种格式的内容，一种带时间的，一种不带时间的，在项目中很可能是由于需求变动导致格式调整引起，假如我们只想查询带有时间的这种数据如何来处理，真实想通过length函数判断长度，发现不能达到目的，不管那种内容返回的长度相同，于是想到如下解决办法，请看SQL。

select age, money, birthday, substr(to_char(birthday,'hh24:mi:ss')

from userinfo where substr(to_char(birthday,'hh24:mi:ss'),1)!= '00:00:00';

结果如下：

这只是同事问我的时候我给出的临时方案，有更好的方法的达人回复我下，谢谢！

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