DBMS 1000+ MCQ with answer for ISRO Recruitment

1. The division operator divides a dividend A of degree m+n by a divisor relation B of degree n and produces a result of degree
A. m - 1
B. m + 1
C. m * m
D. m
Answer : D

2. _______ product was acquired by Informix, integrated into its RDBMS and introduced as the Informix Universal Server an ORDBMS.
A. Star
B. llustar
C. SQL
D. Cygnus
Answer : B

3. _____is a full form of SQL.
A. Standard query language
B. Sequential query language
C. Structured query language
D. Server side query language
Answer : C

4. Relationships among relationships can be represented in an-E-R model using
A. Aggregation
B. Association
C. Weak entity sets
D. Weak relationship sets
Answer : A

5. Which of the following constitutes a basic set of operations for manipulating relational data?
A. Predicate calculus
B. Relational calculus
C. Relational algebra
D. SQL
Answer : C

6. A ____ key specifies a uniqueness constraint that no two distinct tuples in any state r of relation R can have the same value for super key.
A. Sub
B. Parent
C. Candidate
D. Super
Answer : D

7. Which of the following is not comparison operator?
A. <>
B. <
C. =<
D. >=
Answer : C

8. Precedence graphs help to find a
A. Serializable schedule.
B. Recoverable schedule.
C. Deadlock free schedule.
D. Cascadeless schedule.
Answer : A

9. A transaction is in state after the final statement has been executed.
A. partially committed
B. active
C. committed
D. none of the above
Answer : C

10. Create a table with the following attributes: Employee(EMPNO integer, EMPNAME of 10 characters)
A. Create table Employee(EMPNO int, EMPNAME char(10));
B. Create table Employee(EMPNO integer, EMPNAME String(10));
C. Create table Emplo(EMPNO number, EMPNAME string);
D. Create table Emp(EMPNO int, EMPNAME char(10));
Answer : A

11. Use of UNIQUE while defining an attribute of a table in SQL means that the attribute values are
A. distinct values
B. cannot have NULL
C. both (A) & (B)
D. same as primary key
Answer : C

12. _____ command can be used to modify a column in a table
A. alter
B. update
C. set
D. create
Answer : A

13. ______defines the structure of a relation which consists of a fixed set of attribute-domain pairs.
A. Instance
B. Program
C. Schema
D. Super Key
Answer : C

14. Assume transaction A holds a shared lock R. If transaction B also requests for a shared lock on R.
A. It will result in a deadlock situation.
B. It will immediately be rejected.
C. It will immediately be granted.
D. It will be granted as soon as it is released by A .
Answer : C

15. In SQL the statement select * from R, S is equivalent to
A. Select * from R natural join S.
B. Select * from R cross join S.
C. Select * from R union join S.
D. Select * from R inner join S.
Answer : B

16. DBMS is a collection of _____ that enables user to create and maintain a database.
A. Keys
B. Program
C. Translators
D. Language Activity
Answer : B

17. The set of all values that can be taken by the attribute is called as _______ of the attribute.
A. Tuple
B. Cardinality
C. Degree
D. Domain
Answer : D

18. ______contains information that defines valid values that are stored in a column or data type.
A. Default
B. Index
C. Rule
D. View
Answer : B

19. In SQL the word natural can be used with
A. inner join
B. full outer join
C. right outer join
D. all of the above
Answer : A

20. DFD stands for
A. Data Flow Document
B. Data File Diagram
C. Data Flow Diagram
D. Non of the above
Answer : C

21. A data type or format is specified for each _________
A. Relation
B. Tuple
C. Database
D. Domain
Answer : B

22. ………………… approach reduces time and effort required for design and lesser risk in database management.
A. Single global database
B. Multiple databases
C. Top-down approach
D. None of the above
Answer : B

23. Drop Table cannot be used to drop a table referenced by a ______ constraint.
A. Primary Key
B. Local Key
C. Foreign Key
strong>D. Composite Key
Answer : C

24. HSAM stands for ……….
A. Hierarchic Standard Access Method
B. Hierarchic Sequential Access Method
C. Hierarchic Sequential and Method
D. Hierarchic Standard and Method
Answer : B

25. The ______ language consists of SQL statements for operating on the data (insert, Modify, Delete) in tables that already exist.
A. Data Manipulation
B. Data Definition
C. Data Control
D. None
Answer : A

26. Whenever two independent one-to-many relationships are mixed in the same relation, a __________ arises.
A. Functional dependency
B. Multi-valued dependency
C. Transitive dependency
D. Partial dependency
Answer : B

27. In an ER diagram the ___shape specifies the Attibute and a ____ shape specifies the primary key attribute.
A. Oval; An oval with an underlined attribute
B. Circle; A circle with bolded attribute inside it
C. Diamond; A bolded attribute
D. Square; An attribute within the square
Answer : A

28. In an ER model,_____ is described in the database by storing its data.
A. Entity
B. Attribute
C. Relationship
D. Notation
Answer : A

29. The transactions like adding an employee, enrolling a student in a course are examples of _______
A. Logical
B. Physical
C. None
D. Theoretical
Answer : A

30. What are the desirable properties of a decomposition
A. Partition constraint.
B. Dependency preservation.
C. Redundancy.
D. Security.
Answer : B

31. Employees in a company are each assigned their own office, i.e. for each employee there exists a unique office and for each office there exists a unique employee; This statement is an example of ____ type of relation.
A. 1:1
B. 1: Many
C. Many: One
D. Many : Many
Answer : A

32. Which of the following relational algebra operations do not require the participating tables to be union-compatible?
A. Union
B. Intersection
C. Difference
D. Join
Answer : D

33. For correct behaviour during recovery, undo and redo operation must be
A. Commutative
B. Associative
C. idempotent
D. distributive
Answer : C

34. The ______ key of a relation is the attribute (column) or collection of attributes, which uniquely identify a given tuple.
A. Primary
B. Foreign
C. Candidate
D. Alternate
Answer : A

35. _____clause is an additional filter that is applied to the result.
A. Select
B. Order by
C. Group-by
D. Having
Answer : D

36. In 2NF
A. No functional dependencies (FDs) exist.
B. No multivalued dependencies (MVDs) exist.
C. No partial FDs exist.
D. No partial MVDs exist.
Answer : C

37. Immediate database modification technique uses
A. Both undo and redo.
B. Undo but no redo.
C. Redo but no undo.
D. Neither undo nor redo.
Answer : A

38. Which one is correct statement?
Logical data independence provides following without changing application programs:
(i) Changes in access methods.
(ii) Adding new entities in database
(iii) Splitting an existing record into two or more records
(iv) C
A. (i) and (ii)
B. (iv) only
C. (i) and (iv)
D. (ii) and (iii)
Answer : D

39. In a multi-user database, if two users wish to update the same record at the same time, they are prevented from doing so by
A. jamming
B. password
C. documentation
D. record lock
Answer : D

40. The cost of reading and writing temporary files while evaluating a query can be reduced by
A. building indices
B. pipelining
C. join ordering
D. none of the above
Answer : B

41. The common column is eliminated in
A. theta join
B. outer join
C. natural join
D. composed join
Answer : C

42. Which two files are used during operation of the DBMS?
A. Query languages and utilities
B. DML and query language
C. Data dictionary and transaction log
D. Data dictionary and query language
Answer : C

43. What is a disjoint less constraint?
A. It requires that an entity belongs to no more than one level entity set.
B. The same entity may belong to more than one level.
C. The database must contain an unmatched foreign key value.
D. An entity can be joined with another entity in the same level entity set.
Answer : A

44. Data independence means
A. data is defined separately and not included in programs.
B. programs are not dependent on the physical attributes of data
C. programs are not dependent on the logical attributes of data
D. both B and C
Answer : D

45. Which of the following addressing modes permits relocation without any change over in the code?
A. Indirect addressing
B. Indexed addressing
C. PC relative addressing
D. Base register addressing
Answer : B

46. E-R Modeling is achieved by using ____ diagrams
A. DFD
B. Flowcharts
C. Gantt Charts
D. E-R
Answer : D

47. A table can have only one
A. Secondary key
B. Alternate key
C. Unique key
D. Primary key
Answer : D

48. Relations produced from an E-R model will always be
A. First normal form.
B. Second normal form.
C. Third normal form.
D. Fourth normal form.
Answer : A

49. Which of the syntax is correct for insert statement?
i) insert into values
ii) insert into (column list) values
A. i-only
B. ii-only
C. Both of them
D. None of them
Answer : C

50. It is an abstraction through which relationships are treated as higher level entities
A. Generalization.
B. Specialization.
C. Aggregation.
D. Inheritance.
Answer : C