Sample questions

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Thời gian thi: 90 phút
Hình thức thi: lý thuyết (trắc nghiệm + trả lời
ngắn) + bài tập (đề mở)
Cấu trúc bài thi:
◦ A. Lý thuyết tổng hợp
◦ B. Bài tập
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: 2.5đ
: 7.5đ
Thiết kế E(E)RD
: 3đ
Ánh xạ
: 1đ
Viết SQL
: 1.5đ
Bảo mật
: 0.5đ
Chuẩn hóa, tìm khóa : 1.5đ
1. Given the below database schema
1.
a.
b.
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
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(cont.)
Map this schema into ERD
Write SQL statements to:
For each book that is loaned out from the
"Sharpstown" branch and whose DueDate is today,
retrieve the book title, the borrower's name, and
the borrower's address.
For each library branch, retrieve the branch name
and the total number of books loaned out from
that branch
Retrieve the names, addresses, and number of
books checked out for all borrowers who have
more than five books checked out
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Given a relation Emp, the degree of the Emp
relation is?
Given a relation SalGrade, the cardinality of
the SalGrade relation is?
Given a relation Emp, a relation schema of the
Emp relation is?
Given a relation Emp, is it possible to
conclude that the Emp relation is in the first
normal form?

Given a relation Emp, which SQL statements
are used in order to insert into the Emp
relation the data about a new employee
whose empno is 1234, ename is Tam, job is
salesman, MGR is 7698, hire date is
15/07/1996, salary is 1800, and department
is sales
a.
b.
c.
d.
e.
Insert into EMP values(1234, ' Tam', ' salesman ',
7698, TO_DATE(' 15/07/1996', 'DD-MM-YYYY'),
1800, NULL,30);
Insert into EMP values(1234, ' Tam', ' salesman ',
7698, TO_DATE(' 15/07/1996', 'DD-MM-YYYY'),
1800, NULL,(SELECT DEPNO FROM DEPT WHERE
DNAME = ‘Sales”));
Insert into EMP (Empno, Ename, Job, MGR,
HireDate, SAL, DepNo) values(1234, ' Tam', '
salesman ', 7698, TO_DATE(' 15/07/1996', 'DDMM-YYYY'), 1800, 30);
All a, b, and c are correct.
None of them is correct.

Given a relation Emp, which SQL statements
are used in order to insert into the Emp
relation the data about a new employee
whose empno is 2345, ename is Tam, job is
Manager, MGR is Null, hire date is
15/07/1996, salary is 1800, and department
is human resource
a.
b.
c.
d.
Insert into EMP values(2345, ' Tam', ‘Manager ',
NULL, TO_DATE(' 15/07/1996', 'DD-MM-YYYY'),
1800, NULL, NULL);
Insert into EMP values(1234, ' Tam', ' salesman ',
NULL, TO_DATE(' 15/07/1996', 'DD-MM-YYYY'),
1800, NULL,(SELECT DEPNO FROM DEPT WHERE
DNAME = ‘human resource”));
All a, b are correct.
Both a and b are unable to be used for that
insertion because there is no data about the
deparment of human resource in the Dept
relation and the foreign key constraint is
therefore violated.
3. Consider this database with the following
functional depencies (primary key is
(FactoryNumber, ProductNumber) and candidate
key is (FactoryName, ProductNumber))
Production (FactoryNumber, FactoryName,
ProductNumber, Status, Location, QtyOnDay)
 FactoryNumber  FactoryName
 FactoryNumber  Status
 Status  Location
 Location  Status
 FactoryNumber, ProductNumber  QtyOnDay
 FactoryName, ProductNumber  QtyOnDay

Given database with its relation Production as
shown above, which normal form is the
Production relation in?
a. First normal form
b. Second normal form
c. Third normal form
d. Boyce-Codd normal form
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Can you normalize it into the highest level?
Consider the relation R, which has attributes that hold
schedules of courses and sections at a university.
R = {CourseNo, SecNo, OfferingDept,CreditHours, CourseLevel,
InstructorSSN,Semester, Year, Days_Hours,
RoomNo,NoOfStudents}
Suppose that the following functional dependencies hold on R:
{CourseNo} -> {OfferingDept, CreditHours,CourseLevel}
{CourseNo, SecNo, Semester, Year} ->{Days_Hours, RoomNo,
NoOfStudents,InstructorSSN}
{RoomNo, Days_Hours, Semester, Year} -> {InstructorSSN,
CourseNo, SecNo}

Try to determine which sets of attributes form keys of R. How
would you normalize this relation?
Consider the following relation for published books:
BOOK (Book_title, Authorname, Book type Book_type,
Listprice, Author_affil,Publisher)
Author_affil referes to the affiliation of the author
Suppose the following dependencies exist:
Book_title -> Publisher, Book_type
Book Book_type -> Listprice
Author_name -> Author-affil
Find keys and normalize this relation into 3NF
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