B.) to
C.) from
D.) by
[单选题][A] for [B] with [C] into [D] from
[单选题]A. with B to C from D by
[单选题][A] From [B] Under [C] On [D] With
[单选题][A] on[B] from[C] at[D] about
[单选题][A] after [B] since [C] as [D] from
[单选题][A] about[B] around[C] to[D] from
[单选题][A] beneath [B] from [C] under [D] beyond
[单选题]请在(5)处填上最佳答案。[A] with[B] in[C] from[D] by
[单选题][A] in spite of [B] far from [C] rather than [D] by means of
[单选题]设有关系R(A,C)和S(C,D)。与sQL语句 selectA,D from R,S where R.C=S.C等价的关系代数表达式是______。A.πA,D(σR.C=S.C(R×S))B.σR.C=S.C(πA,D(R×S))C.σR.C=S.C(πD(πAR)×S))D.σR.C=S.C(πAR)×(πDS))