A.3NF
B.2NF
C.INF
D.BCNF
[单选题]For relation where primary key contains multiple attributes,no non-key attribute should be functionally dependent on a part of primary key.This relation R is at least in (66) .(66) A.3NFB.2NFC.INFD.BCNF
[单选题]F.or relation where primary key contains multiple attributes, no non-key attribute should be functionally dependent on a part of primary key. This relation R is at least in(66).A.3NFB.2NFC.INFD.BCNF
[单选题]F.or relation R where primary key contains multiple, no non-key attribute should be functionally dependent on a part of the primary key.This relation R is at least inA.1NFB.2NFC.3NFD.BCNF
[单选题]F.or relation R where primary key contains multiple attributes,no non-key attribute should be functionally dependent on a part of the primary key. This relation R is at least inA. 1NFB.2NFC.3NFD.BCNF
[名词解释] 主码(Primary Key)
[单选题]11. —Where is ________ key to the door?—It’s in my pocket.A.aB.theC./D.an
[主观题]在SQL语言中PRIMARY KEY的作用是()。A.定义主码B.定义外部码C.定义处部码的参照表D.确定主码类型
[单选题]在SQL语言中PRIMARY KEY的作用是()。A . 定义主码B . 定义外部码C . 定义处部码的参照表D . 确定主码类型
[主观题]在SQL中可以使用PRIMARY KEY子句对完整性( )
[单选题]Acandidate key is().A.an attribute or a set of attributes with a unique value for each tuple of a relationB.a set of attributes referring to another relation in the databaseC.an attribute or a set of attributes that is potentially the primary key of