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ocp 11g认证考试051题库解析:第41题

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ocp 11g认证考试051题库解析:第41题,完整题库请点击这里联系老师咨询了解

41. Which two statements are true regarding views? (Choose two.)

A. A subquery that defines a view cannot include the GROUP BY clause.

B. A view that is created with the subquery having the DISTINCT keyword can be updated.

C. A view that is created with the subquery having the pseudo column ROWNUM keyword cannot

be updated.

D. A data manipulation language ( DML) operation can be performed on a view that is created with

the subquery having all the NOT NULL columns of a table.

Answer: CD

答案解析:

A错误,创建视图的子查询可以使用group by子句。

B错误,子查询中带有DISTINCT 不能对视图进行DML操作。

C正确,子查询中带有ROWNUM 关键字不能对视图进行DML操作。

D正确,所有非空列都可以进行DML操作。

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