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DBMS MCQ QUESTIONS
MODEL PAPER – 8
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1. What is a "view" in
the context of a Database Management System (DBMS)?
a. A physical storage unit for data
b. A virtual table based on the result of a SELECT query
c. A primary key constraint on a table
d. A unique identifier for a database record
Answer: b. A virtual table based on the result of a SELECT query
2. In a DBMS, what is the primary
purpose of creating views?
a. To store data permanently
b. To improve data security
c. To simplify complex queries and provide a customized presentation of
data
d. To enforce referential integrity
Answer: c. To simplify complex queries and provide a customized
presentation of data
3. Which of the following
statements about views in a DBMS is true?
a. Views are physical tables with actual data stored in them
b. Views cannot be used in SQL queries
c. Views are dynamic and reflect changes in the underlying data
d. Views are primarily used for storing sensitive information
Answer: c. Views are dynamic and reflect changes in the underlying data
4. What is a "materialized
view" in a DBMS?
a. A view with physical data stored in it
b. A view that cannot be modified or queried
c. A view that enforces constraints on data
d. A view without any SELECT statement
Answer: a. A view with physical data stored in it
5. How does a view contribute to
data abstraction in a DBMS?
a. By making data retrieval more complex
b. By hiding the underlying complexity of data from users
c. By limiting the types of queries that can be performed
d. By reducing data security
Answer: b. By hiding the underlying complexity of data from users
6. In a DBMS, what is the
significance of the "WITH CHECK OPTION" clause when creating a view?
a. It allows users to check the integrity of the entire database
b. It restricts data modification to rows that satisfy the view's
defining condition
c. It enforces a primary key constraint on the view
d. It limits the number of rows displayed in the view
Answer: b. It restricts data modification to rows that satisfy the
view's defining condition
7. Which of the following is an
advantage of using views in a DBMS?
a. Increased data redundancy
b. Limited data security
c. Simplified data access and reduced complexity for users
d. Reduced data abstraction
Answer: c. Simplified data access and reduced complexity for users
8. What is the primary difference
between a view and a table in a DBMS?
a. Tables store virtual data, while views store physical data
b. Views are permanent storage units, while tables are temporary
c. Views are based on SELECT queries and do not store physical data,
while tables store physical data
d. Tables are used for complex queries, while views are used for simple
queries
Answer: c. Views are based on SELECT queries and do not store physical
data, while tables store physical data
9. How does a view contribute to
data security in a DBMS?
a. By exposing all data to users
b. By restricting access to certain columns of a table
c. By increasing data redundancy
d. By preventing the use of SQL queries
Answer: b. By restricting access to certain columns of a table
10. What is the role of the
"CREATE VIEW" statement in a DBMS?
a. To create a physical table
b. To create a virtual table based on a SELECT query
c. To enforce constraints on a table
d. To delete a table from the database
Answer: b. To create a virtual table based on a SELECT query
11. What is the purpose of the
"WITH CHECK OPTION" clause in a view definition in a DBMS?
a. To check the integrity of the entire database
b. To enforce a primary key constraint on the view
c. To limit the number of rows displayed in the view
d. To restrict data modification to rows that satisfy the view's
defining condition
Answer: d. To restrict data modification to rows that satisfy the view's
defining condition
12. Which of the following
statements about materialized views is true?
a. Materialized views are dynamic and reflect changes in the underlying
data
b. Materialized views do not store physical data
c. Materialized views are primarily used for data abstraction
d. Materialized views are views without any SELECT statement
Answer: a. Materialized views are dynamic and reflect changes in the
underlying data
13. How does a view contribute to
simplifying data access in a DBMS?
a. By making data retrieval more complex
b. By exposing the underlying complexity of data to users
c. By providing a customized presentation of data
d. By increasing the number of tables in the database
Answer: c. By providing a customized presentation of data
14. In a DBMS, what is the
primary role of the "DROP VIEW" statement?
a. To create a view
b. To delete a view from the database
c. To modify the data in a view
d. To enforce constraints on a view
Answer: b. To delete a view from the database
15. What is the significance of
the "INSTEAD OF" trigger in the context of views in a DBMS?
a. It prevents data modification in a view
b. It enforces constraints on a view
c. It provides an alternative mechanism for handling data modification
operations on a view
d. It limits the types of queries that can be performed on a view
Answer: c. It provides an alternative mechanism for handling data
modification operations on a view
16. Which of the following is a
disadvantage of using views in a DBMS?
a. Increased data redundancy
b. Limited data security
c. Increased complexity for users
d. Reduced data abstraction
Answer: c. Increased complexity for users
17. What is the role of the
"WITH READ ONLY" clause in the definition of a view in a DBMS?
a. To restrict data modification operations on the view
b. To enforce referential integrity on the view
c. To allow only read operations on the view
d. To hide the view from certain users
Answer: c. To allow only read operations on the view
18. How does a view enhance data
independence in a DBMS?
a. By making data retrieval more complex
b. By limiting the types of queries that can be performed
c. By providing a layer of abstraction between users and the underlying
data
d. By exposing the underlying complexity of data to users
Answer: c. By providing a layer of abstraction between users and the
underlying data
19. What is a key benefit of using
views for data reporting in a DBMS?
a. Views do not support data reporting
b. Views provide a direct connection to the underlying data
c. Views simplify the reporting process by presenting a tailored view of
the data
d. Views make the reporting process more complex
Answer: c. Views simplify the reporting process by presenting a tailored
view of the data
20. How does a materialized view
differ from a regular (non-materialized) view in a DBMS?
a. Materialized views are not dynamic and do not reflect changes in the
underlying data
b. Regular views store physical data, while materialized views do
not
c. Materialized views do not support data abstraction
d. Regular views are primarily used for data reporting
Answer: a. Materialized views are not dynamic and do not reflect changes
in the underlying data
21. What is the primary advantage
of using a view in a DBMS for security purposes?
a. Views expose all data to users
b. Views enforce referential integrity
c. Views provide a layer of abstraction, allowing restricted access to
specific columns and rows
d. Views restrict the use of SQL queries
Answer: c. Views provide a layer of abstraction, allowing restricted
access to specific columns and rows
22. What is the purpose of the
"CREATE OR REPLACE VIEW" statement in a DBMS?
a. To create a new table
b. To modify the data in a view
c. To create a view or update it if it already exists
d. To enforce constraints on a view
Answer: c. To create a view or update it if it already exists
23. Which of the following
statements about the relationship between views and tables in a DBMS is true?
a. Views are independent of tables and do not rely on table data
b. Views cannot be based on more than one table
c. Views are directly linked to the underlying tables and reflect
changes in table data
d. Tables are virtual representations of views
Answer: c. Views are directly linked to the underlying tables and
reflect changes in table data
24. What is the significance of
the "WITH CHECK OPTION" clause when modifying data through a view in a DBMS?
a. It allows unrestricted modification of data
b. It enforces referential integrity on the view
c. It restricts data modification to rows that satisfy the view's
defining condition
d. It limits the number of rows displayed in the view
Answer: c. It restricts data modification to rows that satisfy the
view's defining condition
25. In a DBMS, what is the role
of an "INSTEAD OF" trigger associated with a view?
a. To prevent data modification in a view
b. To enforce constraints on a view
c. To provide an alternative mechanism for handling data modification
operations on a view
d. To limit the types of queries that can be performed on a view
Answer: c. To provide an alternative mechanism for handling data
modification operations on a view
26. How does a view contribute to
data integrity in a DBMS?
a. By making data retrieval more complex
b. By exposing the underlying complexity of data to users
c. By providing a layer of abstraction between users and the underlying
data
d. By enforcing data constraints on the view
Answer: d. By enforcing data constraints on the view
27. What is the role of the
"WITH CASCADED CHECK OPTION" clause in a DBMS view definition?
a. To enforce referential integrity on the view
b. To allow unrestricted data modification in the view
c. To restrict data modification to rows that satisfy the view's
defining condition
d. To cascade the check option to related views
Answer: d. To cascade the check option to related views
28. How does a view contribute to
improving query performance in a DBMS?
a. By increasing data redundancy
b. By limiting data retrieval operations
c. By providing a layer of abstraction for complex queries
d. By making the querying process more complex
Answer: c. By providing a layer of abstraction for complex queries
29. What is the primary advantage
of using a view for data reporting in a DBMS?
a. Views do not support data reporting
b. Views provide a direct connection to the underlying data
c. Views simplify the reporting process by presenting a tailored view of
the data
d. Views make the reporting process more complex
Answer: c. Views simplify the reporting process by presenting a tailored
view of the data
30. In a DBMS, what is the
significance of the "WITH READ ONLY" clause when defining a view?
a. To allow only read operations on the view
b. To restrict data modification operations on the view
c. To enforce referential integrity on the view
d. To hide the view from certain users
Answer: a. To allow only read operations on the view
31. What is the primary purpose
of the "WITH CHECK OPTION" clause in a view definition in a DBMS?
a. To prevent data modification in the view
b. To enforce referential integrity on the view
c. To cascade the check option to related views
d. To restrict data modification to rows that satisfy the view's
defining condition
Answer: d. To restrict data modification to rows that satisfy the view's
defining condition
32. How does a view contribute to
data abstraction in a DBMS?
a. By making data retrieval more complex
b. By exposing the underlying complexity of data to users
c. By providing a layer of abstraction between users and the underlying
data
d. By increasing data redundancy
Answer: c. By providing a layer of abstraction between users and the
underlying data
33. What is the primary advantage
of using a view for data security in a DBMS?
a. Views expose all data to users
b. Views enforce referential integrity on the data
c. Views restrict access to specific columns and rows of the underlying
tables
d. Views increase the complexity of data access
Answer: c. Views restrict access to specific columns and rows of the
underlying tables
34. In a DBMS, what is the
purpose of the "WITH CASCADED CHECK OPTION" clause in a view
definition?
a. To enforce referential integrity on the view
b. To cascade the check option to related views
c. To allow unrestricted data modification in the view
d. To restrict data modification to rows that satisfy the view's
defining condition
Answer: b. To cascade the check option to related views
35. What happens when a user
queries a view in a DBMS?
a. Data is physically retrieved from the view
b. Data is physically retrieved from the underlying tables based on the
view's definition
c. Data is stored in the view permanently
d. Data is modified in the underlying tables
Answer: b. Data is physically retrieved from the underlying tables based
on the view's definition
36. What is the role of the
"WITH READ ONLY" clause in a DBMS view definition?
a. To prevent data modification in the view
b. To cascade the check option to related views
c. To restrict access to specific columns of the view
d. To enforce referential integrity on the view
Answer: a. To prevent data modification in the view
37. How does a materialized view
differ from a regular (non-materialized) view in a DBMS?
a. Materialized views are dynamic and reflect changes in the underlying
data
b. Regular views store physical data, while materialized views do
not
c. Materialized views are used for complex reporting, while regular
views are for simple queries
d. Regular views are more efficient for data modification operations
Answer: b. Regular views store physical data, while materialized views
do not
38. What is the purpose of an
"INSTEAD OF" trigger in the context of a DBMS view?
a. To prevent data modification in the view
b. To enforce referential integrity on the view
c. To provide an alternative mechanism for handling data modification
operations on the view
d. To cascade the check option to related views
Answer: c. To provide an alternative mechanism for handling data
modification operations on the view
39. In a DBMS, what does the
"WITH CHECK OPTION" clause do when modifying data through a view?
a. Allows unrestricted modification of data
b. Enforces referential integrity on the view
c. Restricts data modification to rows that satisfy the view's defining
condition
d. Limits the number of rows displayed in the view
Answer: c. Restricts data modification to rows that satisfy the view's
defining condition
40. How does a view contribute to
improving data independence in a DBMS?
a. By exposing the underlying complexity of data to users
b. By making data retrieval more complex
c. By providing a layer of abstraction between users and the underlying
data
d. By restricting access to specific columns of the view
Answer: c. By providing a layer of abstraction between users and the
underlying data
41. What is the primary benefit
of using a materialized view in a DBMS?
a. Materialized views are dynamic and reflect changes in the underlying
data
b. Materialized views improve data security
c. Materialized views provide better performance for certain queries by
precomputing results
d. Materialized views have no impact on query performance
Answer: c. Materialized views provide better performance for certain
queries by precomputing results
42. What is the role of an
"INSTEAD OF" trigger when modifying data through a view in a DBMS?
a. To prevent data modification in the view
b. To enforce referential integrity on the view
c. To provide an alternative mechanism for handling data modification
operations on the view
d. To cascade the check option to related views
Answer: c. To provide an alternative mechanism for handling data
modification operations on the view
43. How does a view contribute to
data consistency in a DBMS?
a. By exposing the underlying complexity of data to users
b. By making data retrieval more complex
c. By providing a layer of abstraction between users and the underlying
data
d. By enforcing data constraints on the view
Answer: d. By enforcing data constraints on the view
44. In a DBMS, what is the
significance of the "WITH READ ONLY" clause when querying a view?
a. To prevent data modification in the view
b. To allow unrestricted data modification in the view
c. To restrict access to specific columns of the view
d. To enforce referential integrity on the view
Answer: a. To prevent data modification in the view
45. What is the primary advantage
of using a view in a DBMS for data reporting purposes?
a. Views do not support data reporting
b. Views provide a direct connection to the underlying data
c. Views simplify the reporting process by presenting a tailored view of
the data
d. Views make the reporting process more complex
Answer: c. Views simplify the reporting process by presenting a tailored
view of the data
46. How does a view contribute to
improving data independence in a DBMS?
a. By exposing the underlying complexity of data to users
b. By making data retrieval more complex
c. By providing a layer of abstraction between users and the underlying
data
d. By restricting access to specific columns of the view
Answer: c. By providing a layer of abstraction between users and the
underlying data
47. What is the primary
difference between a view and a table in a DBMS?
a. Tables store virtual data, while views store physical data
b. Views are permanent storage units, while tables are temporary
c. Views are based on SELECT queries and do not store physical data,
while tables store physical data
d. Tables are used for complex queries, while views are used for simple
queries
Answer: c. Views are based on SELECT queries and do not store physical
data, while tables store physical data
48. What happens when a user
queries a materialized view in a DBMS?
a. Data is physically retrieved from the materialized view
b. Data is physically retrieved from the underlying tables based on the
materialized view's definition
c. Data is stored in the materialized view permanently
d. Data is modified in the underlying tables
Answer: a. Data is physically retrieved from the materialized view
49. In a DBMS, what is the role
of an "INSTEAD OF" trigger when querying a view?
a. To prevent data modification in the view
b. To enforce referential integrity on the view
c. To provide an alternative mechanism for handling data modification
operations on the view
d. To cascade the check option to related views
Answer: c. To provide an alternative mechanism for handling data
modification operations on the view
50. What is the purpose of the
"WITH CHECK OPTION" clause in a view definition in a DBMS?
a. To prevent data modification in the view
b. To enforce referential integrity on the view
c. To cascade the check option to related views
d. To restrict data modification to rows that satisfy the view's
defining condition
Answer: d. To restrict data modification to rows that satisfy the view's
defining condition
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