CCP Database Management & Information Systems 2 — Questions and Answers
Question 1: Which normal form eliminates transitive dependencies in a relational table?
- First Normal Form (1NF)
- Second Normal Form (2NF)
- Third Normal Form (3NF) (Correct answer)
- Boyce-Codd Normal Form (BCNF)
Correct answer: Third Normal Form (3NF)
3NF removes transitive dependencies by ensuring every non-key attribute depends only on the primary key.
Question 2: In a client-server database architecture, where is the DBMS engine typically located?
- On every client machine
- On the server (Correct answer)
- Embedded in each application
- In a cloud-only environment
Correct answer: On the server
In client-server architecture, the DBMS engine runs on the server and processes queries sent by client applications.
Question 3: What does a ROLLBACK statement do in a database transaction?
- Saves all changes permanently
- Undoes all changes made since the last COMMIT (Correct answer)
- Locks the table for other users
- Drops the current transaction log
Correct answer: Undoes all changes made since the last COMMIT
ROLLBACK reverses all data modifications made during the current transaction, restoring the database to its prior state.
Question 4: Which type of JOIN returns only the rows that have matching values in both tables?
- LEFT OUTER JOIN
- RIGHT OUTER JOIN
- FULL OUTER JOIN
- INNER JOIN (Correct answer)
Correct answer: INNER JOIN
An INNER JOIN returns only records where there is a match in both joined tables.
Question 5: What is the purpose of an index in a relational database?
- To enforce referential integrity
- To speed up data retrieval operations (Correct answer)
- To encrypt sensitive columns
- To store backup copies of rows
Correct answer: To speed up data retrieval operations
Indexes create a separate data structure that allows the DBMS to locate rows faster without scanning the entire table.
Question 6: In the E-R model, a relationship in which one entity can be associated with many instances of another entity, but each instance of the second can relate to only one of the first, is called:
- Many-to-many
- One-to-one
- One-to-many (Correct answer)
- Recursive
Correct answer: One-to-many
A one-to-many (1:N) relationship means one record in table A can link to multiple records in table B, but each B record links to only one A record.
Question 7: Which SQL clause is used to filter groups after a GROUP BY operation?
- WHERE
- HAVING (Correct answer)
- FILTER
- ORDER BY
Correct answer: HAVING
HAVING filters the result of GROUP BY aggregations, whereas WHERE filters individual rows before grouping.
CCP Database Management & Information Systems 2
Which normal form eliminates transitive dependencies in a relational table?