DECLARE
  CURSOR CS IS
    SELECT JUNO
       ,ROWID RID
     FROM TABL;
  TYPE CS_TAB  IS TABLE OF CS%ROWTYPE INDEX BY PLS_INTEGER;
  TYPE JUNO_TAB IS TABLE OF TABL.JUNO%TYPE INDEX BY PLS_INTEGER;
  TYPE RID_TAB IS TABLE OF ROWID INDEX BY PLS_INTEGER;
  CS_T  CS_TAB;
  JUNO  JUNO_TAB;
  RID   RID_TAB;
BEGIN
  OPEN CS;
  LOOP
    FETCH CS BULK COLLECT INTO CS_T LIMIT 10000; -- 한번에처리할 ROW수
    EXIT WHEN CS_T.COUNT = 0;
    JUNO.DELETE;
    RID.DELETE;
    FOR I IN 1..CS_T.COUNT
    LOOP
      -- CS_T(I).JUNO를이용 암호화 처리
      JUNO(I) := 암호결과;
      RID(I) := CS_T(I).RID;
    END LOOP;
    FORALL I IN 1..JUNO.COUNT
      UPDATE TABL SET JUNO = JUNO(I) WHERE ROWID = RID(I);
    COMMIT;
  END LOOP;
  CLOSE CS;
END;