下面有关主键的叙述正确的是( ) -题库考试答案搜索网

下面有关主键的叙述正确的是( )

单选题

2021-09-02 00:08

A、不同的记录可以具有重复的主键值或空值
B、一个表中的主键可以是一个或多个字段
C、在一个表中主键只可以是一个字段
D、表中的主键的数据类型必须定义为自动编号或文本

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正确答案

B

试题解析

标签：青书学堂河南工学院数据库原理

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