若规定基本表中某一列或若干列为非空和唯一值双重约束，则这些列就是该基本表的( )码 -题库考试答案搜索网

若规定基本表中某一列或若干列为非空和唯一值双重约束，则这些列就是该基本表的( )码

单选题

2021-07-19 06:30

A、<span style=";font-family:宋体;font-size:14px">主码 </span></p><p><br/></p>
B、<p style="text-indent:28px;line-height:150%"><span style=";font-family:宋体;font-size:14px">候选码</span></p><p><br/></p>
C、外码
D、内码

查看答案

正确答案

B

试题解析

B

标签：计算机网络技术高起专关系型数据库 2020年第二学期期末考试

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