A.3NF B.BCNF C.2NF D.1NF
A.差 B.交 C.并 D.投影
A.數(shù)據(jù)項(xiàng) B.數(shù)據(jù)流圖 C.數(shù)據(jù)存儲(chǔ) D.數(shù)據(jù)結(jié)構(gòu)