0 of 35 questions completed
- 35 Questions (Selected Randomly)
- 35 Marks (1 Mark/Question)
- 40 Minutes of Time
This quiz consists of questions from the Database for GATE 2019 preparation.
All The Best!
You must specify a text.
You must specify an email address.
You have already completed the quiz before. Hence you can not start it again.
Quiz is loading...
You must sign in or sign up to start the quiz.
You have to finish following quiz, to start this quiz:
0 of 35 questions answered correctly
Time has elapsed
You have scored 0 of 0 points, (0)
Question 1 of 35
1. Question1 points
Consider a relational table with a single record for each registered student with the following attributes
1. Registration_number: Unique registration number for each registered student
2. UID: Unique identity number at the national level for each citizen
3. Bank Account_number: Unique account number at the bank. A student can have multiple accounts or join accounts.. This attributes stores the primary account number.
4. Name: Name of the student
5. Hostel_room: room number of the hostel
Which of the following option is incorrect?
Question 2 of 35
2. Question1 points
Relation R with an associated set of functional dependencies F, is decomposed into BCNF. The redundancy ( arising our of functional dependencies) in the resulting set of relation is
Question 3 of 35
3. Question1 points
R(ABCD) is a relation. Which of the following does not have a lossless join, dependency preserving BCNF decomposition?
Question 4 of 35
4. Question1 points
Consider the following relational schema pertaining to a student’s database:
Students (rollno, name, address )
Enroll( rollno, courseno, coursename)
Where primary keys are shown in italics. The number of tuples in the student and Enroll tables are 120 and 8 respectively. What are the maximum and minimum number of tuples that can be present in (Student *Enroll), where * denotes natural join?
Question 5 of 35
5. Question1 points
The following functional dependencies are given below
AB-> CD, AF->D, DE->F, C->G, F->E, and G->A
Which of the following option is false?
Question 6 of 35
6. Question1 points
Suppose the adjacency relation of vertices in a graph is represensed in a table Adj(X,Y) Which of the following queries cannon t be expressed by a relational algebra expression of constant length?
Question 7 of 35
7. Question1 points
The following key values are inserted into a B+ tree in which order of the internal nodes is 3, and that of the leaf nodes is 2, in the sequence below. The ordre of internal nodes is the maximum number of tress pointers in each node, and the order of leaf nodes is the maximum number of data items that can be stored in it. The B+ trees is initially empty. 10, 3, 6, 8, 4, 2, 1 The maximum number of times leaf nodes would get split up as a result of these insertions is
Question 8 of 35
8. Question1 points
With regard to the expressive power of the formal relational query languages, which of the following statements is true?
Question 9 of 35
9. Question1 points
Consider the following schedules involving two transactions. Which one of the following statements is true?
S1: r1(X); r1(Y); r2(X); r2(Y); w2(Y); w1(X)
S2: r1(X); r2(X); r2(Y); w2(Y); r1(Y); w1(X)
Question 10 of 35
10. Question1 points
The following table has two attributes A and C where A is the primary key and C is the foreign key referencing a with on delete cascade.
The set of all tuples that must be additionally deleted to preserve referential integrity when the tuple (2,4) is deleted is
Question 11 of 35
11. Question1 points
Consider a B+ tree in which the maximum number of keys in a node is 5. What is the minimum number of keys in any non-root node?
Question 12 of 35
12. Question1 points
A B+ tree index is to be built on the name attribute of the relation Student. Assume that all students name are of length 8 bytes, disk blocks are of size 512 byte and index pointer are of size 4 bytes. Give this scenario, what would be the best choice of the degree
Question 13 of 35
13. Question1 points
Which of the following statements is false?
Question 14 of 35
14. Question1 points
THE RELATIONAL SCHEMA STUDENT PERFORMANCE(NAME, COURSENO, ROLLNO, GRADE) HAS THE FOLLOWING FUNCTIONAL INDEPENDENCE
NAME, COURSENO -> GRADE
ROLLNO,COURSENO -> GRADE
THE HIGHEST NORMAL FORM OF THIS RELATION SCHEME IS
Question 15 of 35
15. Question1 points
Relation R is decomposed using a set of functional dependencies F, and relation S is decomposed using another set of functional dependencies G. Once decomposition is definitely BCNF , other is definitely 3 NF, but it is not known which is to make a guaranteed identification, which one of the following tests should be used on the decomp0sitions ?( assume that the closure of F and G are available)
Question 16 of 35
16. Question1 points
Let E1 and E2 be two entities in an E/R diagram with simple single-valued attributes. R1 and R2 are two relationships between E1 and E2, where R1 is one to many and R2 is many to many. R1 and R2 do not have any attributes of their own. What is the minimum number of tables required to represent this situation in the relational model?
Question 17 of 35
17. Question1 points
Which of the following concurrency control protocols ensure both conflict serializability and freedom from deadlock?
1. 2 phase locking
2. time stamp ordering
Question 18 of 35
18. Question1 points
The full form of DDL is
Question 19 of 35
19. Question1 points
The order of an internal node in a B+ tree index is the maximum number of children it can have. Suppose that a child pointer takes 6 bytes, the search filed value takes 14 bytes, and the bloc size is 512 bytes. What is the order of the internal node?
Question 20 of 35
20. Question1 points
_____________ function divides one numeric expression by another and returns the remainder.
Question 21 of 35
21. Question1 points
Given the following relation instance
X Y Z
1 4 2
1 5 3
1 6 3
3 2 2
which of the following functional dependencies are satisfied by the instance
Question 22 of 35
22. Question1 points
The employee information in a company is stored in the relation Employee(name,sex,salary,deptname). Consider the following sql query
Select deptname from employee where sex=’m’ group by deptName having avg(salary)>(select avg(salary) from employee)
It returns the name of the department in which
Question 23 of 35
23. Question1 points
The order of a leaf node in a B+ tree is the maximum number of (value, data, record pointer) pairs it can hold. Given that the block size is 1 kb, data record pointer is byte long, the value field is 9 byte long and a block pointer is 6 byte long, what is the order of the leaf node?
Question 24 of 35
24. Question1 points
The relation book(title,price) contains the titles and prices of different books. Assuming that no two books have the same price, what does the following sql query list?
Select title from book as B where (select count(*) from book as T where T.price >B.price)<5
Question 25 of 35
25. Question1 points
Which of the following is a valid SQL type?
Question 26 of 35
26. Question1 points
The following functional dependencies hold for relations R(A, B, C) and S(B, D, E )
The relation R contains 200 tuples and the relation S contains 100 tuples. What is the maximum number of tuples possible in the natural Join R and S?
Question 27 of 35
27. Question1 points
Which of the following is a key factor for preferring B+ tree to binary search trees for indexing database relations?
Question 28 of 35
28. Question1 points
Which of the following is correct?
Question 29 of 35
29. Question1 points
B+ trees are preferred to binary tress in databases because
Question 30 of 35
30. Question1 points
_________ is a virtual table that draws its data from the result of an SQL SELECT statement.
Question 31 of 35
31. Question1 points
Database table by name Loan_Records is given below.
Borrower Bank_Manager Loan_Amount
Ramesh Sunderrajan 100000
Suresh Ramgopal 5000
Mahesh Sunderrajan 7000
What is the output of the following SQL query?
SELECT count(*) From(SELECT Borrower.Bank_Manager From Loan_Records) AS S Natural Join ( SELECT BANK_manager, Loan_Amount From Loan_Records) As T );
Question 32 of 35
32. Question1 points
Which of the following scenarios may lead to an irrecoverable error in a database system?
Question 33 of 35
33. Question1 points
Consider a Schema R(ABCD) and functional dependencies A->B and C->D. Then the decomposition of R into R1(AB) and R2(CD) is
Question 34 of 35
34. Question1 points
Which of the following operations need the participating relations to be union compatible?
Question 35 of 35
35. Question1 points
Count function in SQL returns the number of