第13题: [单项选择]当局部E-R图合并成全局E-R图时可能出现冲突。下面所列举的冲突中,属于上述冲突的是( )。 A. 属性冲突 B. 语法冲突 C. 模式冲突 D. 语义冲突 参考答案:A 答案解析:[解析] 当局部E-R图合并成全局E-R图时可能出现3类冲突:属性冲突、结构冲突和命名冲突。属性和命名冲突通常用讨论、协商等行政手段解决,结构冲突则要认真分析后用技术手段解决。
A. it led to a terrible loss of human life B. it was the earliest kind of flu C. it broke out after World War One D. it infected many animals as well 参考答案:A 答案解析:题干中出现的关键词“Spanish flu”带引号并且有大写这个特征,可以据此很快定位到第二段。A)是对原文killing up to 40 million people with half of t
第22题: [单项选择]All of the following are attributes that can be specified when creating a logical volume EXCEPT:() A. Number of logical partitions B. Disk where logical volume will reside C. Size of the logical volume control block D. Position of the logical volume on the disk 参考答案:C