A.在數(shù)據(jù)庫(kù)中,數(shù)據(jù)存在副本現(xiàn)象,即為數(shù)據(jù)冗余
B.通過(guò)分類存儲(chǔ),可以有效減少數(shù)據(jù)冗余,但會(huì)增加數(shù)據(jù)查找的復(fù)雜度
C.在數(shù)據(jù)庫(kù)設(shè)計(jì)階段,一定要盡可能大得避免數(shù)據(jù)冗余,盡量做到數(shù)據(jù)不冗余
D.數(shù)據(jù)冗余通常是因?yàn)閿?shù)據(jù)庫(kù)數(shù)據(jù)過(guò)多導(dǎo)致的