28 一个数据库系统来说，下列观点中正确的是（） -题库考试答案搜索网

28 一个数据库系统来说，下列观点中正确的是（）

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2021-09-03 17:11

A、一个数据库系统必须具有子模式、模式和存储模式三级
B、一个数据库系统必须具备一定的数据独立性
C、一个数据库系统必须对查询进行优化
D、一个数据库系统不允许存储数据冗余

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正确答案

B@#@B

试题解析

标签：青书学堂平顶山学院数据库原理(专升本)

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