Question

Is there a way to generate unique numbers (int for instance) inside a user defined function?

rand() and newid() do not work due to side-effecting.

Thanks.

Answer 1

CRYPT_GEN_RANDOM gets around the NEWID() limitation

SELECT CHECKSUM(CRYPT_GEN_RANDOM(8000))

So you can use it like this. No “side effecting” error

CREATE FUNCTION dbo.test ()
RETURNS int
AS
BEGIN
   RETURN CHECKSUM(CRYPT_GEN_RANDOM(8000))
END
GO
SELECT dbo.test()