select * from Store.STIPR,Store.STCategory where
iprdate = (case when @IPRdate is null then iprdate else @IPRdate end) and
iprno = (case when @IPRNo is null then iprno else @IPRNo end) and
deliveredto = (case when @DeliveredTo is null then deliveredto else @DeliveredTo end) and
classification = (case when @Classification is null then classification else @Classification end) and
requiredfor = (case when @RequiredFor is null then requiredfor else @RequiredFor end) and
stcategoryID = (case when @STCategoryID is null then stcategoryID else @STCategoryID end) and
mainstatus = (case when @MainStatus is null then mainstatus else @MainStatus end)