[Oracle] Oracle多表级联更新详解

declare 
  CURSOR D_CURSOR_CUS_INFO IS
  select t3.id_       as id_,
       t3.owe_money_  as owe_money_,
       a.heatingArea  as heating_area_
  from T_CUS_OWE_MONEY_2 t2
  left join T_CUS_OWE_MONEY_3 t3 on t2.id_= t3.id_
  left join (select s.bh,  sum(
       case 
         when s.stkbz='0' then nvl(s.mj,0)
         when s.stkbz='1' then 0-nvl(s.mj,0)
       end 
    ) as heatingArea from  sk s  where s.nd = '2008-2009' group by s.bh) a on t2.bh_=a.bh
  where  t3.owe_money_- t2.owe_money_  = a.heatingArea*5 and t3.OWE_MONEY_ > 0;

begin
    FOR everyRow IN D_CURSOR_CUS_INFO
    loop 
     update T_CUS_YEAR_STATUS t
       set t.HEATING_AREA_ = everyRow.HEATING_AREA_,
         t.OWE_MONEY_  = everyRow.owe_money_
       where t.YEAR_ = '2008-2009'
           and t.id_ = everyRow.id_;
     end loop;
    commit;
end;