考试
2021-02-25 12:21:28

(多选题)Which two statements are

题目描述

AThe UNIQUE constraint does not permit a null value for the column.

BA UNIQUE index gets created for columns with PRIMARY KEY and UNIQUE constraints.

CThe PRIMARY KEY and FOREIGN KEY constraints create a UNIQUE index.

DThe NOT NULL constraint ensures that null values are not permitted for the column.

答案解析

[db:答案解析]

A,D

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