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主码(Primary Key)

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相关试题

For relation where primary key contains

[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

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  • For relation where primary key contains

    [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

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  • For relation R where primary key contain

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  • For relation R where primary key contain

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  • 如果已经建立主关键字为仓库号的仓库关系,现在用如下命令建立职工关系<br />CREATE TABLE 职工(职工号 C(5) PRIMARY KEY;<br />仓库号 C(

    [单选题]如果已经建立主关键字为仓库号的仓库关系,现在用如下命令建立职工关系CREATE TABLE 职工(职工号 C(5) PRIMARY KEY;仓库号 C

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  • 如果已经建立了主关键字为仓库号的仓库关系,现在用如下命令建立职工关系<br />CREATE TABLE职工(职工号C(5)PRIMARY KEY,仓库号C(5)REFERENCE仓库,工

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  • 主码(Primary Key)