What is defined as an area outside sea areas A1, A2 and A3?A.AOR-EB.AOR-WC.Coastal and inland watersD.A4
What is defined as an area outside sea areas A1, A2 and A3?
A.AOR-E
B.AOR-W
C.Coastal and inland waters
D.A4
相关考题:
假设关系R(A1,A2,A3)上的函数依赖集F={A1→A2,A1→A3,A2→A3},则函数依赖()。A.A1→A2是冗余的B.A1→A3是冗余的C.A2→A3是冗余的D.A1→A2,A1→A3,A2→A3都不是冗余的
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关系模式R(A1,A2,A3,A4,A5),如果(A1,A2)→A3,(A3,A4)→A5, 则R的候选键为_________。A.(A1,A2);B.(A1,A2,A5);C.(A1,A2,A4);D.(A1,A2,A3,A4);E.(A1, A2, A4, A5)。
【单选题】关系模式R(A1,A2,A3,A4,A5),如果(A1,A2)→A3,(A3,A4)→A5, 则R的候选键为_________。A.(A1,A2)B.(A1,A2,A5)C.(A1,A2,A4)D.(A1,A2,A3,A4)
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