Bug: SQL Server 2012: Stored Procedure using temporary table with an added primary key

Hi!

I tested the execution of the following procedure for SQL Server 2008 and SQL Server 2012.

USE model
GO

CREATE PROCEDURE dbo.Test
AS
BEGIN
   CREATE TABLE #tempTest(id INT NOT NULL);
   ALTER TABLE #tempTest ADD CONSTRAINT PK_#tempTest PRIMARY KEY(id);
   DROP TABLE #tempTest;
END
GO

If I execute this procedure twice times in one transaction it fails for SQL Server 2012:

BEGIN TRANSACTION
EXEC dbo.Test
EXEC dbo.Test
ROLLBACK TRANSACTION
GO

The error message is:

For SQL Server 2008 it works fine.

However,  there is a workaround to create the primary key when creating the temporary table:

ALTER PROCEDURE dbo.Test
AS
BEGIN
   CREATE TABLE #tempTest(id INT NOT NULL CONSTRAINT PK_#tempTest PRIMARY KEY);
   --ALTER TABLE #tempTest ADD CONSTRAINT PK_#tempTest PRIMARY KEY(id);
   DROP TABLE #tempTest;
END
GO

Does anyone have an explanation for this strange behaviour? For me it seems to be a bug.

Br

Mango81