Advance DBMS 1000+ MCQ with answer for XAT

1. In an object oriented model, one object can access data of another object by passing?
A. Instance variable
B. Variable
C. Message
D. Function
Answer : C

2. Which of the following are the properties of entities?
A. Groups
B. Table
C. Attributes
D. Switchboards
Answer : C

3. Which of the following is the unit of signaling speed or modulation rate or the rate of symbol transmission?
A. Data rate
B. Bit rate
C. Signal to Noise Ratio
D. Baud rate
Answer : D

4. The syntax to select all column from the table is
A. select all from tablename
B. select * from tablename
C. select from tablename
D. none of these
Answer : B

5. The ability to modify the conceptual schema without causing any change to the application program is known as
A. Physical data independence
B. Logical data independence
C. External data independence
D. Static data
Answer : B

6. Which of the following is/are error-free channel(s)
i) Noisy channel
ii) Noiseless channel
A. i only
B. ii only
C. Both
D. None of these
Answer : B

7. A …………… is a memory area where data are processed.
A. view
B. trigger
C. cursor
D. none of the above
Answer : C

8. Which of the following is also known as Offline storage ?
A. primary storage
B. secondary storage
C. tertiary storage
D. none of the above
Answer : C

9. The union of primary keys of a related entity becomes …………. Of a relation.
A. primarykey
B. superkey
C. candidatekey
D. foreignkey
Answer : B

10. The command used to delete a particular column in a relation
A. UPDATE
B. DROP
C. ALTER
D. DELETE
Answer : C

11. Select the incorrect statement(s)
i) Shared locks are compatible with each other.
ii) A relation which is in 3NF may have redundancy due to composite keys.
iii) A table in a database can have multiple indexes.
A. i only
B. ii, only
C. ii, iii only
D. none of the above
Answer : D

12. Radio frequencies below ............. are more suitable for omnidirectional applications.
A. 300MHz
B. 1GHz
C. 5GHz
D. 10 GHz
Answer : B

13. The method of access which uses key transformation is known as
A. direct.
B. hash.
C. random.
D. sequential.
Answer : B

14. What does the number of attributes in a relation is called?
A. Cardinality
B. Degree
C. Tuple
D. Order
Answer : B

15. Select the correct statement
i) Aggregate functions work on a group of data and return a single value.
ii) ODBC connects the frontend with the database without considering its compatibility
iii) View definition cant be used at multiple places through with clause .
A. i and ii only
B. ii and iii only
C. i and iii only
D. i only
Answer : A

16. Tertiary storage
A. magnetic tape
B. juke box
C. optical disk
D. All of the above
Answer : D

17. Referential integrity
A. controls relationships between operations of an object
B. controls relationships between instances of a class
C. controls relationships between attributes in a table
D. controls relationships between tables in a database
Answer : D

18. Which of the following concurrency control schemes is not based on serializability property?
A. Two-phase locking
B. Timestamped based locking
C. Graph-based locking
D. none of the above
Answer : C

19. Related fields in a database are grouped to form a
A. data file.
B. data record.
C. menu.
D. bank.
Answer : B

20. In RDBMS, Data is presented as a collection of
A. Relation
B. Table
C. Attribute
D. Entity
Answer : A

21. Which one of the following is provided by a data dictionary ?
A. User data
B. Database structure data
C. Sorted data
D. Functional data
Answer : B

22. Secondary storage
A. magnetic disk
B. magnetic tape
C. juke box
D. cache
Answer : A

23. Technique(s) used for data recovery after any failure
A. Logging
B. Recovery manager
C. Both A and B are true
D. Both A and B are false
Answer : C

24. Expand the acronym OLAP
A. Object Linked Access Program
B. Organizational Architecture Processing
C. Online Analytical Processing
D. none of these
Answer : C

25. Unwanted energy from source other than the transmitter.
A. Attenuation
B. Distortion
C. Delay
D. Noise
Answer : D

26. If the .................... is too much, the receiver may not be able to detect the signal at all or the signal may fall below the noise level.
A. Noise
B. Delay
C. Dispersion
D. Attenuation
Answer : D

27. Which of the following operator preserves unmatched rows of the relations being joined?
A. Inner join
B. Outer join
C. union
D. Intersect
Answer : B

28. UML is stands for
A. Universal Modeling Language
B. Unified Modeling Language
C. United Modeling Language
D. Uni Modeling Language
Answer : B

29. Consider the join of a relation R with relation S. If R has m tuples and S has n tuples,
then the maximum size of join is:
A. mn
B. m+n
C. m+n)/2
D. 2 m+n)
Answer : A

30. Benefit of database normalization is
A. smaller number of tables
B. higher query processing efficiency
C. reduced I/O for most queries
D. reduced data redundancy
Answer : D

31. The degree of the table with 500 rows and 7 columns is
A. 500
B. 7
C. 3500
D. none of these
Answer : B

32. Which of the following aggregate function doesnt ignore NULLs in its results?
A. COUNT
B. COUNT(*)
C. MAX
D. none of these
Answer : B

33. Tape storage is referred to as
A. sequential access storage
B. direct access storage
C. random access storage
D. none of the above
Answer : A

34. A relation which is in 3NF is
A. in 1NF also
B. in 2NF also
C. free from transitive dependencies
D. All of these
Answer : D

35. Full form of CIDR
A. Classful Inter Domain Routing
B. Classless International Domain Routing
C. Classless Inter Domain Routing
D. none of these
Answer : C

36. Only one communication channel is needed rather than n channels to transmit data between two communicating devices
A. parallel
B. serial
C. analog
D. digital
Answer : B

37. A logical schema
A. is the entire database.
B. is a standard way of organizing information into accessible parts.
C. describes how data is actually stored on disk.
D. both A) and C)
Answer : A

38. Log into a computer across an internet
A. IMAP
B. TELNET
C. POP3
D. Infrared
Answer : B

39. The minimal set of super key is called
A. Primary key
B. Secondary key
C. Candidate key
D. Foreign key
Answer : C

40. An entity set which have sufficient attributes to form a primary key
A. Tree structure
B. Subtree structure
C. Strong entity set
D. Table structure
Answer : C

41. When all attributes in a relation tuple are not functionally dependent only on the key attribute. Which of the following normalization is needed?
A. first
B. second
C. third
D. fourth
Answer : C

42. An advantage of the database management approach is
A. data is dependent on programs.
B. data redundancy increases.
C. data is integrated and can be accessed by multiple programs.
D. none of the above.
Answer : C

43. Which one of the following statements is false?
A. The data dictionary is normally maintained by the database administrator.
B. Data elements in the database can be modified by changing the data dictionary.
C. The data dictionary contains the name and description of each data element.
D. The data dictionary is a tool used exclusively by the database administrator.
Answer : B

44. The index table has …… Columns.
A. 1
B. 2
C. 3
D. 4
Answer : B

45. A lock that allows concurrent transactions to access different rows of the same table is known as a
A. Field-level lock
B. Row-level lock
C. Table-level lock
D. Database-level lock
Answer : A

46. Which of the following statements is not true about two tier client server database architecture?
A. SQL statements are processed on tier server
B. SQL statements may be processed on some of the clients
C. Business logic is mostly processed on clients
D. Business logic may be processed on the server
Answer : C

47. Which of the following submit and execute query at run time?
A. Static SQL
B. Dynamic SQL
C. both
D. none of these
Answer : B

48. In case of entity integrity, the primary key may be
A. not Null
B. Null
C. both Null & not Null.
D. any value.
Answer : A

49. QBE
A. Query By Execution
B. Query By Example
C. Query By Extraction
D. None of the above.
Answer : B

50. B-Tree is used for
A. searching data
B. storing data
C. both A and B
D. none of these
Answer : A