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1、注：试题字迹务必清晰，书写工整。 本题4页，本页为第1页教务处试题编号： 四川大学期末考试试题（闭卷） （2007-2008 学年第 2学期） 课程号： 31113740 课序号： 课程名称： 数据库系统原理（B卷）任课教师： 张天庆 适用专业年级：软件工程2006级 学生人数： 340印题份数： 350 学号： 姓名： 考试须知 四川大学学生参加由学校组织或由学校承办的各级各类考试，必须严格执行四川大学考试工作管理办法和四川 大学考场规则 。有考试违纪作弊行为的，一律按照四川大学学生考试违纪作弊处罚条例进行处理。 四川大学各级各类考试的监考人员，必须严格执行四川大学考试工作管理办法 、 四川
2、大学考场规则和四川大 学监考人员职责 。有违反学校有关规定的，严格按照四川大学教学事故认定及处理办法进行处理。 题 号 一 二 三 四 五 六 七 八 九 十 得 分 阅卷教 师 阅卷时 间 总 成 绩 100 期末卷面50 %半期测验 10 % 平时练习 10 % 项目练习30 %课程名称：数据库系统原理 任课教师： 张天庆 学号： 姓名： 本题3页，本页为第2页 教务处试题编号： 1. Multiple Choices. (2points10) (1) If relation R has n tuples and relation S has m tuples, the minimum n
3、umber of tupes that RS can contain is _. A. max (n,m) B. min (n,m) C. |n-m| D. n+m (2) Which of the following statements are true. I. 4NF implies BCNF II. BCNF implies 3NF. III. 3NF implies BCNF A. None B. I only C. I and II D. I and III (3) The FD X - Y is a full dependency in a relation R, if ther
4、e is _ attribute A that can be _ X and the dependency still holds. A. at least one, added to B. at least one, removed from C. no, added to C. removed from (4) An exclusive lock on a data item represents permission to perform which of the operations, read and write, on the data item? A. Both read and
5、 write. B. Write only. C. Read only. D. Neither read nor write. (5) In a two-phase locking protocol, what happens during the shrinking phase? A. The transaction cannot acquire locks, but can release its locks. B. The transaction can acquire locks, but cannot release its locks. C. The transaction can
6、 acquire locks, and can release its locks. D. The transaction can acquire locks, and can release its locks as long as the number of released locks is greater than the number of acquired locks. (6) The term physical data independence refers to the ability to change A. the conceptual schema without ch
7、anging the application programs B. the physical layout of the data without changing the external schemas, the conceptual schemas, or the application programs C. the application programs without changing the conceptual schema D. the data without physically relocating the tables (7) What attributes do
8、es a subclass have? A. Just the attributes from the superclass B. All the attributes of its superclass, and possibly more C. A subset of the attributes of its superclass D. None of the attributes of its superclass (8) Hashing exhibits the best performance for A. equality searches involving the key,
9、provided the key is used for hashing B. range queries C. sequential scan of the entire table D. ordering query results based on the key used for hashing (9) In an ER model, what is the degree of a relationship type? A. The number of entity types participating in the relationship type B. The strength
10、 of the relationship type课程名称：数据库系统原理 任课教师： 张天庆 学号： 姓名： 本题3页，本页为第3页 教务处试题编号： C. The number of instances of the relationship type D. The validity of the relationship type (10)In a two-phase locking protocol, what happens when a transaction requests a conflicting lock? A. The transaction immediately a
11、cquires the lock from the current lock-holder. B. The transaction proceeds without acquiring the lock. C. The transaction is blocked to acquire the lock. D. The transaction is aborted immediately. 2. Write SQL statements.(5points6) Consider the following relational schema describing an atlas(地图集) :
12、continent (name, area) country (name, continent, population) province (name, country, capital, population) city (name, country, province) Write SQL statements in SQL92 to perform the following instructions. (1) List the name of the countries of the continent whose name begins these letters:as in alp
13、hbetical order. (2) Give the number of cities for each country in the continent whose name is asia in ascending order. (3) List the name of all countries with more than ten cities. (4) Give the name of the country that have the most cities. (5) List the countries name in the continent asia that have
14、 a lager population than any of the countries of europe. (6) For each country , list its name and the number of its cities. 3. Design an E/R diagram for a hospital according to the following information. (15points) The relevant information: A given doctor can prescribe many drugs for a certain patie
15、nt. A patient might be treated by many doctors and can be prescribed the same drug by different doctors. A prescription can involve more than one patient (e.g. a mother and her baby), more than one drug, but is associated with a unique doctor. 4. Convert the following E-R schema into a relational schema using the mapping algorithm specified in this course. Specify keys and referential integrity constraints, using directed arcs. Make sure you also identify alternate keys. Label each step of the mapping algorithm. （15points）
