Question

In a stored procedure (using SQL Server 2008 R2 SP2) is it possible to return a NewSequentialID() without a temp table variable?

I can successfully obtain the NewSequentialID() by using a temp table:

Getting Value of NEWSEQUENTIALID() on Insert

Perhaps I’m old school, but I try to refrain from using temp tables unless absolutely necessary… though this might be a case where it is absolutely necessary…

IF I try:

DECLARE @NewSequentialID UNIQUEIDENTIFIER;
SET @NewSequentialID = NEWID()

… it works as expected.

IF I try:

DECLARE @NewSequentialID UNIQUEIDENTIFIER;
SET @NewSequentialID = NEWSEQUENTIALID()

… I receive the following error:

The newsequentialid() built-in function can only be used in a DEFAULT
expression for a column of type ‘uniqueidentifier’ in a CREATE TABLE
or ALTER TABLE statement. It cannot be combined with other operators
to form a complex scalar expression.

• Is the ONLY solution to use a temp table method?
• Does anyone know of a reason why Microsoft implemented a difference between NEWSEQUENTIALID() to work like NEWID()?
• Anyone know if there’s a chance Microsoft will update NEWSEQUENTIALID() to work like NEWID()?

Geo

UPDATE —
I’m not sure why Microsoft choose to implement the method in this manner, since they state that, “NEWSEQUENTIALID is a wrapper over the Windows UuidCreateSequential function”… but it appears that there is no non-temp-variable table method. (At least as of yet.)
Thanks for everyone’s comments / answers. [Moderator Note:] I’m not sure what to do with a question when the answer is “not possible”. So I’m going to give @marc_s credit for detailing a workaround.

Answer 1

For now – newsequentialid() can only be used as a default constraint on a column. That’s what the error message pretty clearly says, too.

So in order to get your sequential GUID’s – you must have a table. No other way to do this. And no other way in SQL Server 2012, either.

I have no idea nor any information as to why there’s such a difference, and why Microsoft chose to implement it this way….

Update:

OK, so you need to get that value that is being inserted into your table – how about using the OUTPUT clause?

Something like:

DECLARE @NewIDs TABLE (NewSeqID UNIQUEIDENTIFIER)

INSERT INTO dbo.YourTable(list-of-columns)
OUTPUT INSERTED.NewSeqID INTO @NewIDs(NewSeqID)
VALUES (.........)

This way, the output from the INSERT operation – the newly created sequential GUIDs – is being stored into that table variable, and you can use that, return it, slice it – whatever you like!