共找到 892454 与我给老外说canimakeafriendwithyou 相关的结果,耗时1509 ms
设有关系模式R(A,B,C,D,E,F),若有如下的函数依赖集F={A→B,(C,A)→D, (E,F)→A, (E,B)→F, (E,C)→F},若将R分解为3个关系模式R1(A,B), R2(C,A,D),R3(C,E,F,A),则关系模式R2的规范化程度最高达到( )。A.2NFB.3NFC
A.(C, B, D, A, P, E, I, J, G, H)B.(C, B, D, A, E, F, I, G, J, H)C.(B, A, D, E, F, G, I, J, H, C)D.(B, C, D, A, E, F, I, J, G, H)
A.(C, B, D, A, F, E, I, J, G, H)B.(C, B, D, A, E, F, I, G, J, H)C.(B, A, D, E, F, G, I, J, H, C)D.(B, C, D, A, E, F, I, J, G, H)
A.O(n2)B.O(nlogn)C.O(d,n+d,rd)D.O(n)
A.{A}{A,B,C,D,E}{A,B,C,D,E,F,G,H,I,J,K}B.{F}{G}{H}{I}{J}{K}{B,F,G}{C,H}{D,I,J}{E,K}{A,B,C,D,E,E,G,H,I,J,K}C.{K}{J}{I}{H}{G}{F}{B}{C}{D}{E}{A,B,C,D,E,
A.{A}{A,B,C,D,E}{A,B,C,D,E,P,G,H,I,J,K}B.{F}{G}{H}{I}{J}{K}{B,F,G}{C,H}{D,I,J}{E,K}{A,B,C,D,E,F,G,H,I,J,K}C.{K}{J}{I}{H}{G}{F}{B}{C}{D}{E}{A,B,C,D,E,
热门搜索: