如果希望更新表authors中的first_name列为非空，那么可以使用哪个语句？（） -题库考试答案搜索网

如果希望更新表authors中的first_name列为非空，那么可以使用哪个语句？（）

单选题

2022-01-10 23:49

A、alter table authors add first_name not null
B、alter table authors modify first_name not null
C、alter table authors alter first_name not null
D、alter table authors drop first_name not null

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正确答案

B

试题解析

标签： Oracle认证考试 Oracle认证综合练习 CMS专题

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