Is there an exclusive OR operator in T-SQL?

Question

This is my statement

IF (@UserName IS NULL AND @EditorKey IS NULL) OR (@UserName IS NOT NULL AND @EditorKey IS NOT NULL) BEGIN
    RAISERROR (\'One of @UserName,         


        

Answer 1

As a cheat, you can do:

If @UserName+@EditorKey is null and coalesce(@UserName,@EditorKey) is not null

It's shorter, but that may be the only thing it has going for it.

Answer 2

Not very succinct, but you could expand out the logic like this:

WHERE
    (NOT ((@UserName IS NOT NULL) AND (@EditorKey IS NOT NULL))) AND
    ((@UserName IS NOT NULL) OR (@EditorKey IS NOT NULL))

Or use the bitwise XOR operator (^):

WHERE
    (CASE WHEN (@UserName IS NOT NULL) THEN 1 ELSE 0 END) ^
    (CASE WHEN (@EditorKey IS NOT NULL) THEN 1 ELSE 0 END) = 1

You can use a similar approach where there are three or four parameters, and exactly one must have a value:

WHERE
    (CASE WHEN (@Var1 IS NOT NULL) THEN 1 ELSE 0 END) +
    (CASE WHEN (@Var2 IS NOT NULL) THEN 1 ELSE 0 END) +
    (CASE WHEN (@Var3 IS NOT NULL) THEN 1 ELSE 0 END) +
    (CASE WHEN (@Var4 IS NOT NULL) THEN 1 ELSE 0 END) = 1

Answer 3

There's a bitwise XOR, but it's not necessarily what you want:

http://msdn.microsoft.com/en-us/library/ms190277.aspx

In your particular case, I find it more immediate to rewrite it like so:

IF (@UserName IS NULL) = (@EditorKey IS NULL) BEGIN