orcale 匿名代码块

declare 
  cursor readflow_cur is
  select * from od_readflow t where t.flowid is null;
  l_emp od_readflow%rowtype;
begin
  open readflow_cur;
   loop
       fetch readflow_cur into l_emp;
       exit when readflow_cur%notfound;
       update od_readflow r set r.flowid = (select d.flow_id from od_docinfo d where d.bill_id = l_emp.flowinstanceid) where r.readid = l_emp.readid; 
   end loop;
   commit;
   close readflow_cur;

end;