Homework Six
CS325 Database Management Systems
Spring 2009
Date Assigned: 3-5-2009
Problem One:
Consider the database shown above.
Specify the following queries on the relational schema shown above using SQL DML. Describe IN
ENGLISH, how the query works. Also show the result of each query as it would apply to the database
shown above.
a)
Retrieve the names of all senior students majoring in ‘CS’ (Computer Science)
b)
Retrieve the names of all courses taught by Professor King in 1998 and 1999.
c)
For each section taught by Professor King, retrieve the course number, semester, year, and number of
students who took the section.
d)
Retrieve the name and transcript of each senior student (Class = 5) majoring in CS. A transcript includes
course name, course number, credit hours, semester, year, and grade for each course completed by the
student.
e)
Retrieve the names and major departments of all straight-A students (students who have a grade of A in all
of their courses).
f)
Retrieve the names and major departments of all students who do not have a grade of A in any of their
courses.
Grading Criteria:
Each sub-problem receives a maximum of 5 points. Maximum grade for problem is 30 points. Each problem is
graded differently with the cost of an error weighted by the underlying principle of the problem.
Problem Two:
Consider the relational database shown above.
Specify the following queries on the relational schema shown above using SQL DML. Describe IN
ENGLISH, how the query works. Also show the result of each query as it would apply to the database
shown above.
a)
Retrieve the department number, number of employees, combined salary, and average salary for each
department.
b)
Retrieve the department number and number of employees for each department with a combined salary
over $100,000.
c)
Retrieve the department number and average salary for any department with more employees than
department 4.
d)
Consider the following view, DEPT_SUMMARY, defined on the COMPANY database:
CREATE VIEW DEPT_SUMMARY(DNO, COUNT, SUM_SALARY, AVERAGE_SALARY)
AS
SELECT DNO, COUNT(*), SUM(SALARY), AVG(SALARY)
FROM EMPLOYEE
GROUP BY DNO;
Is the following UPDATE possible? Why or why not?
UPDATE
e)
DEPT_SUMMARY
SET DNO = 3
WHERE DNO = 4;
Consider the view from problem (d).
Is the following DELETE possible? Why or why not?
DELETE
FROM DEPT_SUMMARY
WHERE COUNT > 4;
Grading Criteria:
Each sub-problem receives a maximum of 5 points. Maximum grade for problem is 30 points. Each problem is
graded differently with the cost of an error weighted by the underlying principle of the problem.