1000+ Advance DBMS MCQ for JEE Main [Solved]

1. Count function in SQL returns the number of
A. values.
B. distinct values.
C. groups.
D. columns.
Answer : A

2. 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

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

4. Encoding method which does not provide for synchronization
A. B8ZS
B. Manchester
C. RZ
D. NRZ-L
Answer : D

5. Technique used in log based recovery
A. Immediate database modification
B. Graph-based recovery
C. key dependencies
D. none of the above
Answer : A

6. 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

7. The access protocol used by traditional Ethernet
A. CSMA/CA
B. CSMA/CD
C. CSMA
D. Token ring
Answer : B

8. It is possible to define a schema completely using
A. VDL and DDL.
B. DDL and DML.
C. SDL and DDL.
D. VDL and DML.
Answer : B

9. Which of the following is true statement ?
A. SQL permits attribute names to be repeated in the same relation.
B. a SQL query automatically eliminates duplicates.
C. a SQL query will not work if there are no indexes on the relations
D. None of these
Answer : D

10. Every Boyce-Codd normal form is in
A. 3NF
B. 2NF
C. 1NF
D. none of the above
Answer : D

11. Which of the following produces the relation that has attributes of R1 and R2
A. Cartesian product
B. Difference
C. Intersection
D. Product
Answer : A

12. In two-phase locking
A. the data items are locked in growing phase.
B. the data items are released in shrinking phase.
C. Both A and B are true
D. Both A and B are false
Answer : C

13. The maximum number of children in a B-tree of order m is
A. m+1
B. m
C. m-1
D. m/2
Answer : B

14. What does a field or a combination of fields that has a unique value called ?
A. Foreign key
B. Secondary key
C. Primary key
D. Alternate key
Answer : C

15. A relation is said to be in ………. If it doesnt contain partial dependency
A. 1NF
B. 2NF
C. 3NF
D. BCNF
Answer : B

16. 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

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

18. 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

19. An association of several structure of a data base can be expressed graphically by?
A. Tuple
B. Record
C. Relationship
D. Field
Answer : C

20. In the architecture of a database system external level is the
A. physical level.
B. logical level.
C. conceptual level
D. view level.
Answer : D

21. 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 : B

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

23. EEPROM
A. Electrically Extractable Programmable Read Only Memory
B. Electrically Erasable Programmable Read Only Memory
C. Electronically Erasable Programmable Read Only Memory
D. Electrically Erasable Programmable Read Only Memory
Answer : D

24. What are the different types of radio waves that are used for computer network applications?
i) Spread spectrum
ii) High power, single frequency
iii) High power, multiple frequency
iv) Low power, single frequency
v) Low power, multiple frequency br>A. i, ii and iii only
B. i, ii and iv only
C. ii, iii and iv only
D. i, iii and iv only
Answer : B

25. Which of the following normalization is needed, if an attribute of a composite key is dependent on an attribute of the other composite key?
A. BCNF
B. Second
C. Third
D. Fourth
Answer : A

26. The mode in which data item may be locked
A. Partner
B. Mutual
C. Exclusive
D. Atomic
Answer : C

27. …………… is responsible for using that the database remains in a consistent state despite system failure.
A. Storage manager
B. Admin
C. Transaction manager
D. none of the above
Answer : C

28. Which of the following will NOT eliminates the ambiguities of a null value?
A. Define the attribute as required
B. Define subtypes
C. Define each attribute as having an initial value that is recognized as blank
D. Define supertypes
Answer : D

29. A composite attribute is converted to individual attributes in which of the following normal form ?
A. first
B. Second
C. third
D. fourth
Answer : A

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

31. The number of cursors depend on the
A. number of queries
B. number of attributes
C. size of memory area
D. none of these
Answer : C

32. 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

33. 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

34. which of the following is a binary operation?
A. project
B. select
C. rename
D. none of the above
Answer : D

35. 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

36. Usenet is also known as
A. Newsgroups
B. 10Km to 1Km
C. 10^3Km to 100Km
D. 100M to 10M
Answer : A

37. Symbol to represent weak entity set in ER Model
A. Dotted rectangle
B. Square
C. Doubly outlined rectangle
D. Diamond
Answer : C

38. Volatile storage
A. loses its contents when power is switched off.
B. doesnt loses its contents when power is switched off.
C. creates backup when power is switched off.
D. none
Answer : A

39. The exists construct returns the value true, if the argument subquery is
A. empty
B. nonempty
C. contains null values
D. none of the above
Answer : B

40. In this data model each record can hae more than one parent
A. Hierarchical model
B. E-R model
C. Network based model
D. none of these
Answer : C

41. An entity set that does not have sufficient attributes to form a primary key is a
A. strong entity set.
B. weak entity set.
C. simple entity set.
D. primary entity set.
Answer : B

42. In an E-R diagram attributes are represented by
A. rectangle.
B. square.
C. ellipse.
D. triangle.
Answer : C

43. Range variables are designed using the
A. TO clause
B. FROM clause
C. RANGE clause
D. none of the above
Answer : C

44. In defining the notion of the tuple variable, which one of the clause is useful?
A. as
B. by
C. from
D. none of the above
Answer : A

45. Data integrity refers to
A. the uniqueness of the data in a database
B. the correctness and completeness of the data in a database
C. the un redundancies of the data in a database
D. Data independence of the database
Answer : B

46. 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

47. Which of the following is not proper state of transaction ?
A. Partially aborted
B. Partially committed
C. Aborted
D. Committed
Answer :

48. Select the incorrect statement(s)
i) Foreign key values can be left blank
ii) In SQL duplicates may be present
iii) Theta join operation doesnt remove duplicate columns.
iv) NULL value means string of blank characters.
A. i ,iii only
B. ii, iv only
C. iii, iv only
D. ii, iii, iv
Answer : C

49. A transaction which may not complete its execution successfully is termed as
A. Failed
B. Aborted
C. Blocked
D. Finished
Answer : B

50. For large networks, _______ topology is used
A. Ring
B. Bus
C. Mesh
D. none of these
Answer : A