第8题: [单项选择]用户或应用程序看到的那部分的局部逻辑结构的描述是 A. 模式 B. 物理模式 C. 子模式 D. 内模式 参考答案:C 答案解析:[解析] 数据库具有概念模式、外模式和内模式三级结构及外模式/模式映象、模式/内模式映象二层映象。概念模式是对数据库中全部数据的整体逻辑结构的描述,它由若干个概念记录类型组成。外模式又称子模式或用户模
第9题:[单选题]when my mom was out, I was the one taking care of them A. They often ask her for advice. B. They want the woman to give them a litter bit of her knowledge. C. They woman take care of them when her mother is out. D. All of the above. 参考答案:D