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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