A.改進的性能 B.數(shù)據(jù)的完整性和一致性 C.可用性和易于維護 D.用戶安全
A./ B.* C.|| D.#
A.selectseq.ROWNUM from dual B.selectseq.ROWID from dual C.selectseq.CURRVAL from dual D.selectseq.NEXTVAL from dual