皮皮学，免费搜题
登录
搜题
【单选题】
下列关于关系数据库视图的说法中，错误的是( )。 Ⅰ、视图是关系数据库3级模式中的内模式 Ⅱ、视图能够对机密数据提供一定的安全保护 Ⅲ、视图对重构数据库提供了一定程度的逻辑独立性 Ⅳ、所有的视图都是可以更新的 Ⅴ、对视图的一切操作最终都要转换为对基本表的操作A.
Ⅰ、Ⅱ和Ⅲ
B.
Ⅰ和Ⅳ
C.
Ⅱ、Ⅲ和Ⅳ
D.
都正确
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
反馈参考答案：
举一反三
【单选题】During the press conference, the reporters ______ some of the president's statement.,
A.
asked
B.
questioned
C.
challenged
D.
delivered
【单选题】－－－－－What about going to the movies after the conference tomorrow? －－－－－－____ I’m concerned, some
A.
33.-----What about going to the movies after the conference tomorrow? ------____ I’m concerned, some other arrangement would be satisfactory. A．As long as
B.
As far as
C.
As well as
D.
As soon as
【单选题】Some of the members were late for the conference, but I can’t remember _____.
A.
what.
B.
when.
C.
which.
D.
whom.
【简答题】关于scanner构造器不包括的是?
【单选题】约60％足月儿和80％以上的早产儿可于（）
A.
生后1～2天出现黄疸
B.
生后2～3天出现黄疸
C.
生后2～4天出现黄疸
D.
生后2～5天出现黄疸
E.
生后2～6天出现黄疸
【简答题】电化学是研究出现在一个()和一个()界面上的各种效应的科学。
【单选题】It was on the last day ______ a press conference was held by some committee members.
A.
where
B.
that
C.
when
D.
how
【单选题】At the conference he expressed some personal views which brought him into ______ with the Party leadership.
A.
action
B.
crisis
C.
conflict
D.
power
相关题目：
参考解析：
知识点：
题目纠错 0
发布
