How to do that?

>Make it into table-valued UDF.
>
>>
>>I have a view that calculates the Stock Balance upto current date. It is working for me.
>>
>>

>>SELECT     tmp.mcat_code, tmp.mat_code, Mat.mcat_desc, Mat.mat_desc, SUM(tmp.qty) AS qty
>>FROM         (SELECT     mcat_code, mat_code, SUM(qty) AS qty
>>                       FROM          mat_ob
>>                       GROUP BY mcat_code, mat_code
>>                       UNION
>>                       SELECT     mcat_code, mat_code, SUM(qty) AS qty
>>                       FROM         Purchase
>>                       GROUP BY mcat_code, mat_code
>>                       UNION
>>                       SELECT     mcat_code, mat_code, SUM((con_qty + wst_qty) * - 1) AS qty
>>                       FROM         Production
>>                       GROUP BY mcat_code, mat_code ) AS tmp INNER JOIN
>>                      Mat ON Mat.mcat_code + Mat.mat_code = tmp.mcat_code + tmp.mat_code
>>GROUP BY tmp.mcat_code, tmp.mat_code, Mat.mcat_desc, Mat.mat_desc
>>ORDER BY tmp.mcat_code, Mat.mat_desc
>>

>>
>>What i do if I want stock balance for certain date. Parameterized view? how to create it?
>>
>>Zahid