declare
  type rowids is table of rowid;
  cursor c is
    select rowid from test1 where 你要update的条件;
  v_rowid rowids;
begin
  open c;
  loop
    fetch c bulk collect
      into v_rowid limit 100000;--控制提交的记录条数
 
    forall i in 1 .. v_rowid.count
      update test1 a set /*update 字段*/ where a.rowid = v_rowid(i); 
   
  commit;
   
    exit when c%notfound;
  end loop;
  close c;

end;