问题 填空题

在分布式数据库中可将数据库分割成被称为()的逻辑单位,它们可以被分配到不同站点上进行存储。

答案

参考答案:结点

解析:

在分布式数据库系统中,每一个结点是一个独立的数据库系统,每个结点是由它的本地的“真实的”数据库、本地用户、本地DBMS和事务管理软件以及本地的数据通信管理器组成。

阅读理解

阅读理解。

     During the summer holidays there will be a changed schedule of services for the students. Changes for

dining-room and library service hours and for bus schedules will be put up on the wall outside of the

dining-hall. Weekly film and concert schedules will be put up each Wednesday outside of the student club.

     In the summer holidays. buses going to the town centre will leave the gate every hour on the half hour

during the day. The dining room will serve three meals a day from 7:00 am to 7:00 pm during the week and

two meals from noon to 7:00 pm on weekends. The library will be open at its usual hours during the week,

but have shorter hours on Saturdays and Sundays. The weekend hours are from noon to 5:00 pm.

     Students must have a new summer card if you want to use the library lending services. This

announcement will also be seen in the nest week`s student newspaper.

1. This announcement is to ______.

A. tell students of important schedule changes

B. tell students of new bus and library services

C. show the excellent services for students

D. ask students to change their library cards

2. From this passage we know ______.

A. there is a film each week in the student club

B. there is a film or a concert each week in the student club

C. there is a film or a concert on every Wednesday in the student club

D. there will be no changes about the schedules of the weekly film and concert during the summer holidays

3. At which of the following times will the bus leave the gate?

A. 8:00, 9:00,10:00, 11:00

B. 8:30, 9:30, 10:30, 11:30

C. 8:00, 9:00, 10:30, 11:00

D. 8:00, 9:30, 10:00, 11:30

4. In the summer holidays, the library will have ______.

A. no special hours

B. special hours on weekdays

C. special hours on weekends

D. special hours both on weekdays and weekends

5. We may know that during the summer holidays _______.

A. Few students will stay in the university

B. No breakfast will be served on weekends

C. The student newspaper will sell more copies

D. There will be a concert or a film each Wednesday

问答题 简答题