You can create UDF in Sql 2000. Here's the sample of such function.

-- =============================================
-- Create scalar function (FN)
-- =============================================
IF EXISTS (SELECT * 
	   FROM   sysobjects 
	   WHERE  name = N'test_function')
	DROP FUNCTION test_function
GO
CREATE FUNCTION test_function 
	(@dt datetime, 
	 @p2 int)
RETURNS int
AS
BEGIN
	RETURN CASE 
		WHEN @p2=1 THEN DATEPART(yy, @dt)  -- Year
		WHEN @p2=2 THEN DATEPART(mm, @dt)  -- Month
		WHEN @p2=3 THEN DATEPART(dd, @dt)  -- Day
		ELSE Null END
END
GO
USE pubs 
SELECT dbo.test_function(ord_date,2), * FROM sales

>Hi all,
>
>In VFP, I can do a SQL Select like this :
> SELECT cnoee,cname,dage(demas.dbirth) FROM demas
>
>If I want to do the same in SQL Server, do I create a User Defined Function for dage in "Enterprise Manager"?
>
>Can someone direct me the correct direction? Some short syntax would be greatly appreciated, :) . If I want to analyse the age of the employee by passing a date, how will I accomplish that? Normally I will pass dage(demas.dbirth,pdanalysis) where pdanalysis is the private variable..
>
>Regards.