FIX: User Defined Function Returns Incorrect Result for SELECT Statement with DEFAULT Keyword That References a View (308826)

SYMPTOMS

SQL Server 2000 returns incorrect results if you use the DEFAULT keyword with a user defined function (UDF) in a SELECT statement that references a view.

RESOLUTION

To resolve this problem, obtain the latest service pack for Microsoft SQL Server 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

290211 INF: How to Obtain the Latest SQL Server 2000 Service Pack

WORKAROUND

To work around this problem, you can force SQL Server to pass the exact value into the SELECT statement instead of using the DEFAULT keyword. To do this, first query the function and store the default value in a temporary variable. Then, you can use the variable to query the UDF while referencing a view. For example, you can use these statements to query the UDF:

declare @tmp sql_variant 
select @tmp = dbo.test_udf(default) 
select top 1 dbo.test_udf(@tmp) as view_retval from pubs..testauthors

The SELECT statement returns the expected result.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

This problem was first corrected in Microsoft SQL Server 2000 Service Pack 2.

MORE INFORMATION

To reproduce the problem, execute the following code on SQL Server 2000:

Use pubs
go
CREATE VIEW testauthors
AS SELECT * FROM authors
GO
create function test_udf (@i sql_variant  = 'x')
returns sql_variant
as
begin
        return( @i )
end
go
select top 1 dbo.test_udf( default ) as tbl_retval from pubs..authors
select top 1 dbo.test_udf( default ) as view_retval from pubs..testauthors
go
drop function test_udf
drop view testauthors
go

Note that the first SELECT statement returns the expected value of x; however, the second SELECT statement returns an incorrect value of 0.