A.FROM B.GROUPBY C.select D.WHERE E.ORDER BY
A.命名沖突 B.語(yǔ)法沖突 C.結(jié)構(gòu)沖突 D.屬性沖突
A.數(shù)據(jù)流 B.數(shù)據(jù)項(xiàng) C.數(shù)據(jù)存儲(chǔ) D.數(shù)據(jù)結(jié)構(gòu) E.處理過(guò)程