Which two statements are true about simple views? (Choose two.) A) Views can be created as read only. B) Views are data segments like tables. C) Views can be created on the basis of more than one table. D) Data manipulation language (DML) operations cannot be performed on views.
Answer: A,C 视图是一个表或多个表的逻辑表示,普通视图其本身不具有任何数据。 简单视图是指基于单个表建立的,不包含任何函数、表达式和分组函数据的视图。 视图可以以read only模式建立,简单视图上可以进行DML操作 关于C选项,假如是简单视图,是只能基于一个表建立的,但是视图可以由多个表连接产生,所以该题存疑,因为题目问的是简单视图
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