Using a single column table (Identity)?

Question

Why do I need one column table (identity column)? Is there a good use case?

Is this really good practice?

Answer 1

I think people use this for Oracle SEQUENCE replication. Basically, they want to have a unique unique identifier for any object that they create on their system, so they have something like this:

CREATE PROCEDURE dbo.GenerateIdentifier
    @Identifier INT OUTPUT
AS
BEGIN
    SET NOCOUNT ON;

    INSERT dbo.SingleColumnTable DEFAULT VALUES;

    SET @Identifier = SCOPE_IDENTITY();
END
GO

Now, when they want to add a new contact or customer or order, etc., they first call this procedure and get a new identifier. Then only one object in the system will have identifier = 1 or 2, etc.

Answer 2

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Answer 7

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But this is definitely good practice as a table with tables or numbers.