plsql更新超级大库

declare  cursor c is    select rowid from id_card_no;begin  for v_emp in c loop    update id_card_no icn set icn.fixed = '' where icn.rowid = v_emp.rowid;    update id_card_no icn set icn.fixed = regexp_substr(icn.id_card_no,'\d{18}|\d{17}x|\d{17}X|\d{15}') where icn.rowid = v_emp.rowid;    commit;  end loop;end;