设有关系R(A,B,C),在下列的等式中,不成立的是
A.σA<2(πA,B(R))=πA,B(σA<2(R)
B.πA,C(σA<2(R)=σA<2(πA,C(R))
C.πB,C(σA<2(R)=σA<2(πB,C(R))
D.πA(ЛA,B(R))=πA(R)
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Questions 59-60 are based on the following information
A hash table With hash function
H1(k)=k mod 13
Is shown below.
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