IF (EXISTS (select proc_name from sysprocedure where LCase(proc_name)=LCase('SpaGetSericeQtyForOtchet'))) THEN
Drop function SpaGetSericeQtyForOtchet
END IF

GO

CREATE FUNCTION "DBA"."SpaGetSericeQtyForOtchet"(in ServiceNum integer,in FirstInvNo integer,in LastInvNo integer)
returns integer
begin
  declare qty integer;
  select sum(a.Qty) into qty
    from SpaArticles as a,SpaInvoices as i
    where(a.ServiceNo=ServiceNum)
    and(a.Invoiceno>=FirstInvNo and a.InvoiceNo<=LastInvNo)
    and i.CancelInvoiceNo=0
    and a.InvoiceNo=i.InvoiceNo;
  if qty is null then
    return(0)
  else
    return(qty)
  end if
end