本文章来介绍一篇SQLite DateTime日期时区问题解决方法和一些小方法的应用介绍，有需要的朋友可以参考一下哈。
对于MSSQL中常见的DateDiff函数取两个日期间的天数差，在SQLite 中，有一个函数julianday，可以替换使用。
用法就是：julianday(datetime())-julianday(CreateTime) --CreateTime 是列名。
一直以来，都习惯性这么用，今天有点需求，同一点击在1天内有效，一开始写成：where julianday(datetime())-julianday(CreateTime) =0
经过调试之后，发现这里犯了几个错误。
1：julianday(datetime())-julianday(CreateTime)的差值出来的不是整数，是浮点数，所以不会等于0那么巧。
而datediff(d,getdate(),'2011-10-13 11:11:11') 出来的，是整数，这是一点区别。
2：datetime()，默认取的值是UTC时间，和我们默认的时间就产生时差，换成datetime('now','localtime')，就好了。
于是，最终正确的写法就成了：where julianday(datetime('now','localtime'))-julianday(CreateTime)
OK，本文就小小记录到这里了
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