Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

Empdt1(empcode, name, street, city, state,pincode).For any pincode, there is only one city and state. Also, for given street, city and state, there is just one pincode. In normalization terms, empdt1 is a relation in

A. 1 NF only
B. 2 NF and hence also in 1 NF
C. 3NF and hence also in 2NF and 1NF
D. BCNF and hence also in 3NF, 2NF and 1NF
Answer» C. 3NF and hence also in 2NF and 1NF
Discussion
2.

The relation employee(ID,name,street,Credit,street,city,salary) is decomposed intoemployee1 (ID, name)employee2 (name, street, city, salary)This type of decomposition is called

A. Lossless decomposition
B. Lossless-join decomposition
C. Both a and b
D. None of the mentioned
Answer» E.
Discussion
3.

Inst_dept (ID, name, salary, dept name, building, budget) is decomposed intoinstructor (ID, name, dept name, salary)department (dept name, building, budget)This comes under

A. Lossy-join decomposition
B. Lossy decomposition
C. Lossless-join decomposition
D. Both a and b
Answer» E.
Discussion
4.

There are two functional dependencies with the same set of attributes on the left side of the arrow:A->BCA->BThis can be combined as

A. A->BC
B. A->B
C. B->C
D. None of the mentioned
Answer» B. A->B
Discussion
5.

Consider a relation R(A,B,C,D,E) with the following functional dependencies:ABC -> DE andD -> ABThe number of superkeys of R is:

A. 2
B. 7
C. 10
D. 12
Answer» D. 12
Discussion
6.

Suppose we wish to find the ID s of the employees that are managed by people who are managed by the employee with ID 123. Here are two possible queries:I.SELECT ee.empID FROM Emps ee, Emps ff WHERE ee.mgrID = ff.empID AND ff.mgrID = 123;II.SELECT empID FROM Emps WHERE mgrID IN (SELECT empID FROM Emps WHERE mgrID = 123);Which, if any, of the two queries above will correctly (in SQL2) get the desired set of employee ID s?

A. Both I and II
B. I only
C. II only
D. Neither I nor I
Answer» B. I only
Discussion
7.

Suppose relation R(A,B) currently has tuples {(1,2), (1,3), (3,4)} and relation S(B,C) currently has {(2,5), (4,6), (7,8)}. Then the number of tuples in the result of the SQL query:SELECT * FROM R NATURAL OUTER JOIN S;

A. 2
B. 4
C. 6
D. None of the mentioned
Answer» B. 4
Discussion
8.

Suppose now that R(A,B) and S(A,B) are two relations with r and s tuples, respectively (again, not necessarily distinct). If m is the number of (not necessarily distinct) tuples in the result of the SQL query: R intersect S;Then which of the following is the most restrictive, correct condition on the value of m?

A. M = min(r,s)
B. 0 <= m <= r + s
C. Min(r,s) <= m <= max(r,s)
D. 0 <= m <= min(r,s)
Answer» E.
Discussion