mysql中时间字段datetime怎么判断为空
mysql中时间字段datetime如何判断为空
mysql中时间字段datetime初始值是 0000-00-00 00:00:00
如何去判断为空
如果为空就更新到系统时间
否则就不更新
------解决方案--------------------
判断 某表的一字段 == 0000-00-00 00:00:00 要是等就更新，否则就不更新
这样不就行了吗？为什么非要判断空呢？
------解决方案--------------------
貌似没有更好的办法了，只能判断字符串是否相等。
------解决方案--------------------
是这样的
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