假设关系R(A1，A2，A3)上的一个分解为ρ={(A1，A2)，(A1，A3)}，下表是关系R上的一个实例，根据实例推出R的函数依赖集F为（ ），分解p（ ）。
问题1选项
A.F={A1→A2}
B.F={A1A3→A2,A1A2→A3}
C.F={A1→A3}
D.F={A1→A2,A1→A3}
问题2选项
A.是无损联接的
B.是保持函数依赖的
C.是有损联接的
D.无法确定是否保持函数依赖
正确答案及解析
正确答案
解析
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