General Database Management MCQs

1. An ODMG object model cannot use exceptions for reporting errors.

2. Data dictionary can be used for which of the following options? 1. For f‌inding the location of the data. 2. For f‌inding the size of the storage disk. 3. For finding the owner of the data.

3.

Which of the following inference rules for functional dependencies are correct?

1. |fA> BandA>C,thenA> BC

2. lfA>BC,thenA>BandA>C

3. |fA> B and DB>C,then DA>C

4.lfA>BandC>D.thenAC>BD

4. Which of the following statements is incorrect?

5. Which of the following RAID levels is widely used to store log f‌iles in a database system?

6. Which of the following statements correctly describes a transitive dependency?

7. What do you mean by backflushing in the construction of a data warehouse?

8. Data dictionary can be used for which of the following options? 1. For f‌inding the location of the data. 2. For f‌inding the size of the storage disk. 3. For f‌inding the owner of the data.

9. What is the use of the TRUNCATE command in SQL?

10. Any user-defined Object in an Object model that is not a type of collection object is called a/an _.

11. In a database, transactions follow ACID properties. Which of the following are these properties?

12. Which of the following levels of the data-storage virtualization technology involves bit-level striping with dedicated Hamming-code parity?

13. Which of the following access control policies ensures a high degree of protection from malicious attacks?

14. An Object-oriented database stores persistent object(s) that is/are not shared among multiple applications or programs, in a permanent storage.

15. Object Query Language (OOL) is based on which of the following data models?

16. Which of the following statements about a distributed database is false?

17. Which of the following syntaxes are used for inserting data into a table? (1) INSERT INTO table_name VALUES (value1,value2, value3,...); (2) INSERT INTO table_name (columnl. column2. column3,...) VALUES (valuel. value2. valueB....); (3) INSERT INTO table_name1 [(column1, column2, column3, .....) ] SELECT column1.column2.co|umn3. FROM table_name2 [WHERE condition];

18. Which Of the given figures represents a weak entity as used in Entity-Relationship (ER) diagrams?

19. A tablespace is divided into .

20. Consider a relation 'Book' with the following structure: book_id (Primary key) book_name book_title date_of_issue Which of the following relational algebra operations will return all the entries of book_id and book_title from the relation 'Book'?

21. The index in which the search key defines an order that is dissimilar from the sequential order of the file is known as index.

22. Which of the following statements is false?

23. A covert channel permits the transfer of information in such a way that it violates the system's security policy.

24. Which of the following options is defined as the tendency to change the internal schema without affecting the conceptual schema?

25. Which of the following levels of a data storage virtualization technology involves block-level striping with distributed parity?

26. Which one of the given options is not a component of a storage manager in a database management system?

27. A database table must have only one primary key and one super key.

28. Which attributes is represented by the entity-relationship (E-R) diagram given in the image?

29. Suppose there are two relations: R1 and R2. If C1 and C2 are the selection conditions, and A1 and A2 are the attributes of the relation R1, then which of the given query transformations are correct? 1. 0C1 (0C1 (R1)) -> 0C2 (0C2 (R1)) 2. 0C1 (nA1 (R1)) -> nAl (0C1 (R1)) 3. 0C1 (R1 U R2) -> 0C1 (R1) U 0C1 (R2)

30. Which database security mechanisms is used to enforce multilevel security by classifying users and data into various security levels? 1. Mandatory security mechanisms 2. Discretionary security mechanisms

31. Which of the given options is targeted and focused on a single subset of an organization?

32. Consider a table named 'Account,' having the following fields.

33. Which of the following relational algebra expressions represents the query that will f‌ind names of customers having an account balance of over Rs. 5.000?

34. In which areas data-mining technology can be applied? 1. Marketing 2. Finance 3. Manufacturing 4. Healthcare

35. Which of the following correlated SQL queries will return Employeeld. EmployeeName, Salary and Department of all the employees whose salary is more than the average salary of employees in their respective departments?

36. Which of the following statements will be used to delete all the records from a table named, th? 1. DELETE from tb1; 2. DELETE ‘ from tb1; 3. DELETE tb1;

37. 1. SELECT Iast_name, salary, hire_date FROM EMPLOYEES ORDER BY salary DESC 2. SELECT Iast_name, salary. hire_date FROM EMPLOYEES ORDER BY 2 DESC

38. How can a timestamp be implemented in a database?

39. Which of the following is NOT the correct syntax to write the REVOKE statement that is used to revoke a privilege on a table named, Employee from user2?

40. Which type of constraints are expressed by the application programs and not directly expressed in the schemas Of the data model?

41. Consider a table titled 'StudentDetails' having the following attributes:

42. Which of the following SOL queries will return the details of only those students who are enrolled in the 'Cricket' club?

43. Choose the incorrect statements about an object identif‌ier (01D)? 1. The value of an OlD is visible to an external user. 2. It is used by a system to identify Objects uniquely. 3. An OID cannot be assigned to variables in programs.

44. Database normalization is used to .

45. Which of the following relations is also called a snapshot relation?

46. Which of the following indexes in databases is usually dense?

47. What is the order of execution of operations during a pessimistic concurrency control technique?

48. Concurrency control is used .

49. A database system without concurrency control may cause:

50. The hash address space in static hashing is not always the same.

51. Restriction of_ from the basic relational model has been removed in the nested relational model.

52. Consider the schema R = (ABCD) and the functional dependencies A -> B, B -> C, C -> D and D -> A. Let R = (R1 and R2) be a decomposition, such that R1 {'1 R2 = cp. The decomposition is in .

53. Which of the following statements about normal forms is/are true?

54. ____ yields better performance.

55. ________ involves standardizing the format of data retrieved from different systems.

56. A ____ is a column in a table that describes a characteristic about a record.

57. A ________ is the smallest component in the computer system data hierarchy.

58. A star schema contains both fact and ________ tables.

59. An entity cluster is formed by combining multiple interrelated entities into ____.

60. Data that are never physically altered once they are added to the store are called ________ data.

61. If b (an attribute) is functionally dependent on a, we can also say that ____.

62. In the data hierarchy, the smallest element is the _____.

63. Information in the data dictionary is called: _______________

64. Only one ____ constraint can exist for each table.

65. The catalog is maintained by ____.

66. The field ______ defines the maximum number of characters a field can contain.

67. When a subquery is used, ____ is(are) evaluated first.

68. The ________ states that no primary key attribute may be null.

69. A ________ view is materialized when referenced.

70. The index key can have multiple attributes, this is called a(n) ____________________ index.

71. To make changes to existing data in a table, you would use the ____ command.

72. To normalize a data structure, you apply the ______________________ in sequence.

73. A(n) ____ is the equivalent of a field in a file system.

74. 1nf, 2nf, and 3nf are ____.

75. ________ tools and techniques process data and do statistical analysis for insight and discovery.

76. ________ problems are encountered when removing data with transitive dependencies.

77. A struct is a(n) ____________________, not a declaration.

78. The ____ macro action will move the focus to a specific control.