UNIQUE NullAble

一般情况 UNIQUE 不应该出现nullable的

但是如果我们要支持也是有办法的，就是写一个filter.

https://msdn.microsoft.com/en-us/library/ms187019.aspx <--参考

right click add New Index 时记得关掉table，打开的话是不允许add的.

set 好一般的UNIQUE后, 在filter 加上 ([columnName] IS NOT NULL) 就可以了.

时间： 2024-11-18 22:29:14

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