Easier to do this:ALTER PROCEDURE [dbo].[sp_SHOW_APPROVALS_WITH_COALESCE]@REQUESTOR varchar(100) =NULL,@REQUEST_TYPE_T varchar(100) =NULL,@APPROVED_T varchar(100) =NULLASBEGINSELECT @REQUESTOR = NULLIF(@REQUESTOR,'ALL'),@REQUEST_TYPE_T = NULLIF(@REQUEST_TYPE_T,'ALL'),@APPROVED_T = NULLIF(@APPROVED_T,'ALL')SELECT *FROM PRIME_MASTER_APPROVALSWHEREREQUEST_TYPE_T = COALESCE(@REQUEST_TYPE_T,REQUEST_TYPE_T) ANDREQUESTOR = COALESCE(@REQUESTOR,REQUESTOR) ANDAPPROVED_T = COALESCE(@APPROVED_T,APPROVED_T)
Be advised that using the COALESCE technique will not give the best performance.