oracle 存储过程

create or replace function f_get_ticket_month_money(p_line_id in integer,p_bg_date in date,p_ed_date date) return number is
  Result number(10,2);
begin
  begin
  select sum(b.n_money) into result from erp_ticket_submit_month b
         where b.d_sell>=p_bg_date and b.d_sell<=p_ed_date and b.i_line_id=p_line_id;
exception when others then null;
end ;
  return(Result);
end f_get_ticket_month_money;