A. 從員工數(shù)據(jù)庫(kù)中檢索每個(gè)部門(mén)的平均工資 B. 從員工數(shù)據(jù)庫(kù)中檢索每個(gè)部門(mén)的總工資 C. 從員工數(shù)據(jù)庫(kù)中檢索工資額相等的部門(mén) D. 從員工數(shù)據(jù)庫(kù)中檢索工資額不等的部門(mén)
A. delete * from user where name=”jack” B. drop from user where name=”jack” C. alter from user where name=”jack” D. delete user where name=”jack”
下面三條語(yǔ)句的執(zhí)行結(jié)果為()
A.刪除掉 ‘產(chǎn)品數(shù)據(jù)庫(kù)’ B.把‘產(chǎn)品數(shù)據(jù)庫(kù)’改名為’product’ C.刪除掉‘product’ D.把’product’改名為‘產(chǎn)品數(shù)據(jù)庫(kù)