DBMS 1000+ MCQ with answer for DRDO

1. Which of the following concurrency control schemes is not based on the serializability property?
A. Two - phase locking
B. Graph-based locking
C. Time-stamp based locking
D. None of these .
Answer : D

2. ______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

3. What is data integrity?
A. It is the data contained in database that is non redundant.
B. It is the data contained in database that is accurate and consistent.
C. It is the data contained in database that is secured.
D. It is the data contained in database that is shared.
Answer : B

4. Change Staff table by removing default of Assistant for position column
A. ALTER TABLE Staff ALTER position DROP DEFAULT;
B. ALTER TABLE Staff ALTER position DEFAULT;
C. ALTER TABLE Staff ALTER DROP DEFAULT;
D. MODIFY Staff ALTER position DROP DEFAULT;
Answer : A

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

6. The data in the database at a particular moment of time is called the _______
A. Snapshot
B. Dynaset
C. Stateless
D. Stateful
Answer : A

7. Grant and revoke are _____ statements.
A. TCL
B. DCL
C. DDL
D. DML
Answer : B

8. Relational Algebra is
A. Data Definition Language .
B. Meta Language
C. Procedural query Language
D. None of the above
Answer : C

9. 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

10. 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

11. DROP is a statement in SQL.
A. Query
B. Embedded SQL
C. DDL
D. DCL
Answer : C

12. If an entity can belong to only one lower level entity then the constraint is
A. disjoint
B. partial
C. overlapping
D. single
Answer : B

13. Checkpoints are a part of
A. Recovery measures.
B. Security measures.
C. Concurrency measures.
D. uthorization measures.
Answer : A

14. 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

15. A relation is in attribute of other composite key. if an attribute of a composite key is dependent on an
A. 2NF
B. 3NF
C. BCNF
D. 1NF
Answer : B

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

17. Key to represent relationship between tables is called
A. primary key
B. secondary key
C. foreign key
D. none of the above
Answer : C

18. Which of the following is not a consequence of concurrent operations?
A. Lost update problem.
B. Update anomaly.
C. Unrepeatable read.
D. Dirty read.
Answer : B

19. A ______ module is typically designed so that it will run on a user workstation or personal computer.
A. Software
B. Server
C. Program
D. Client
Answer : D

20. A relational database developer refers to a record as
A. an attribute
B. a tuple
C. a criteria
D. a relation
Answer : B

21. Which of the following relational algebraic operations is not from set theory?
A. Union
B. Intersection
C. Cartesian Product
D. Select
Answer : D

22. The graphical representation of a query is .
A. B-Tree
B. graph
C. Query Tree
D. directed graph
Answer : C

23. 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

24. When an E-R diagram is mapped to tables, the representation is redundant for
A. weak entity sets
B. weak relationship sets
C. strong entity sets
D. strong relationship sets
Answer : B

25. A _____ is used to define overall design of the database
A. code
B. data definition language
C. application program
D. schema
Answer : D

26. 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

27. 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

28. 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

29. The _______ is a set of programs to use and / or modify this data.
A. DBMS
B. System
C. Program
D. Software
Answer : A

30. 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

31. Consider the join of relation R with a relation S. If R has m tuples and S has n tuples, then the maximum and minimum size of the join respectively are
A. m+n and 0
B. m+n and |m-n|
C. mn and 0
D. mn and m+n
Answer : C

32. 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

33. 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

34. The full form of GUI is _________
A. Government Union Internet
B. Graphical Unit Interface
C. Graphical User Interface
D. Graphical University Interface
Answer : C

35. The _____ category includes storage media that can be operated on directly by the computers central processing unit.
A. Primary storage
B. Secondary Storage
C. All
D. Tertiary Storage
Answer : A

36. _______ 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

37. The keyword to eliminate duplicate rows from the query result in SQL is
A. DISTINCT
B. NO DUPLICATE
C. UNIQUE
D. None of the above
Answer : C

38. The data models defined by ANSI/SPARC architecture are
A. Conceptual, physical and internal
B. Conceptual, view and external
C. Logical, physical and internal
D. Logical, physical and view
Answer : D

39. ______is a special type of integrity constraint that relates two relations & maintains consistency across the relations.
A. Domain Integrity Constraints
B. Referential Integrity Constraints
C. Domain Constraints
D. Entity Integrity Constraints
Answer : B

40. The clause alter table in SQL can be used to
A. add an attribute
B. delete an attribute
C. alter the default values of an attribute
D. all of the above
Answer : D

41. An outstanding functionality of SQL is its support for automatic_____ to the target data.
A. programming
B. navigation
C. functioning
D. notification
Answer : B

42. Shadow paging has
A. no redo
B. no undo
C. redo but no undo
D. neither redo nor undo
Answer : A

43. If a transaction T has obtained an exclusive lock on item Q, then T can
A. read Q
B. write Q
C. both read and write Q
D. write Q but not read Q
Answer : C

44. The language that requires a user to specify the data to be retrieved without specifying exactly how to get it is
A. Procedural DML.
B. Non-Procedural DML.
C. Procedural DDL.
D. Non-Procedural DDL.
Answer : B

45. DBMS helps achieve
A. Centralized control of data
B. Data independence
C. Both A and B
D. Neither A nor B
Answer : C

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

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

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

49. Union operator is a :
A. Unary Operator
B. Ternary Operator
C. Binary Operator
D. Not an operator
Answer : C

50. The fact that information in the data warehouse changes far less often and may be regarded as non-real-time with periodic updating; This implies that data warehouses are _______
A. Volatile
B. Non - Volatile
C. Logical
D. Physical
Answer : B