关系中组成主键的属性不能取空值，这称为关系的（）。 -题库考试答案搜索网

关系中组成主键的属性不能取空值，这称为关系的（）。

单选题

2021-07-17 23:12

A、<span style="FONT-FAMILY: 宋体; FONT-SIZE: 14pt; mso-ascii-font-family: ">实体完整性</span><span lang="EN-US" style="FONT-SIZE: 14pt"></span><p></p><p></p>
B、<span style="FONT-FAMILY: 宋体; FONT-SIZE: 14pt; mso-ascii-font-family: ">关系完整性</span><span lang="EN-US" style="FONT-SIZE: 14pt"></span><p></p><p></p>
C、<span style="FONT-FAMILY: 宋体; FONT-SIZE: 14pt; mso-ascii-font-family: ">参照完整性</span>
D、<span style="FONT-FAMILY: 宋体; FONT-SIZE: 14pt; mso-ascii-font-family: ">主键完整性</span><span lang="EN-US" style="FONT-SIZE: 14pt"></span><p></p><p></p>

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正确答案

A

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标签：计算机科学与技术（脱产）专升本数据库系统概论平时作业1 期末考试

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