[exercise 5] [Database Principle]

One . Single topic selection

1. stay SQL Of SELECT In the sentence , What can realize projection operation is ( ).
A. SELECT
B. FROM
C. WHERE
D. GROUP BY
right key : A

2.SQL Set data query 、 Data manipulation 、 Data definition and data control function are integrated , sentence ALTER TABLE Which of the following functions ( ).
A. Data query
B. Data manipulation
C. Data definition
D. Data control
right key : C

3. The following SQL In the sentence ,( ) Not data manipulation statements .
A. INSERT
B. CREATE
C. DELETE
D. UPDATE
right key : B

4.SQL in , The following operations involving null values , What's not right is ( ).
A. AGE IS NULL
B. AGE IS NOT NULL
C. AGE = NULL
D. NOT (AGE IS NULL)
right key : C

5. If you use the following SQL Statement creates a table S:
CREATE TABLE S
(SNo CHAR (6) NOT NULL,SName CHAR(8) NOT NULL,SEX CHAR(2),AGE INTEGER)
Now S When inserting a table, such as the following line , Which line can be inserted ( )?
A. (‘991001’ , ‘ Li Mingfang ’, Woman , ‘23’)
B. (‘990746’, ‘ Zhang Wei ’, NULL, NULL)
C. (NULL, ‘ Chen Daoyi ’, ‘ male ’, 32)
D. (‘992345’, NULL, ‘ Woman ’, 25)
right key : B

6. Suppose the student relationship is S(SNo,SName,Sex,Age), The curriculum relationship is C(CNo,CName,Teacher), What is the relationship between students' course selection SC(SNo,CNo,Grade). To find “ database ” Curriculum “ male ” The student's name , The relationship to be involved is ( ).
A. S
B. SC,C
C. S,SC
D. S,C,SC
right key : D

7. stay SQL in , The command to modify the data table structure is ( ).
A. ALTER
B. CREATE
C. CHANGE
D. DELETE
right key : A

8. Known students 、 The three relationships between courses and grades are as follows : Student ( Student number , full name , Gender , class )、 Course ( Course name , Class hours , nature )、 achievement ( Course name , Student number , fraction ). If you print student transcript , Including student ID 、 full name 、 Course name and score , These relationships should be ( ) operation .
A. and
B. hand over
C. The product of
D. Connect
right key : D

Two . Short answer

1. Set up teaching database school There are the following relational patterns in , Use them separately SQL Complete the following questions .

student( Student number , full name , Gender , Date of birth , Class number )
course( Course no. , Course name , The teacher )
score( Student number , Course no. , fraction )

(1) Inquire about student Names of all records in the table 、 Gender and class number column .

(2) In ascending order of course number , The scores are displayed in descending order score All the records of the table .

(3) Check the names of all students 、 Course number and score column .

right key ：
(1) Inquire about student Names of all records in the table 、 Gender and class number column .

SELECT   full name , Gender , Class number   FROM  student

(2) In ascending order of course number , The scores are displayed in descending order score All the records of the table .

SELECT  *  FROM score  ORDER BY   Course no.  ASC, fraction  DESC

(3) Check the names of all students 、 Course number and score column .

SELECT  student. full name ,score. Course no. ,score. fraction   FROM  student,score  
WHERE  student. Student number =score. Student number