There cannot be more than one one row with Null value in the Unique index because Nulls are treated as duplicate values for indexing purposes.


>The SQL Server Books Online says the NULL values are not '=', but when I set up a Nullable Unique field, and try to import data into it, I get a 'Violation of UNIQUE KEY constraint'. If I turn the constraint off, it works OK, but I need the constraint, and I need it to be Nullable.
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>Am I going to be able to do this??
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>Thank You in advance!
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>Rollin