Rigorous Rdbms Test - 66+ MCQs: RDBMS test: Evaluate Your Database Management Knowledge with RDBMS Questions and Answers

1. What is normalization in the context of database design?

Reducing redundancy and dependency

Increasing data redundancy

Optimizing query performance

Enhancing data encryption

2. Examine the role of the EXPLAIN statement in SQL and how it can be used to optimize queries.

The EXPLAIN statement provides insight into the query execution plan, allowing database administrators to analyze and optimize query performance.

The EXPLAIN statement is used to execute queries and has no impact on optimization.

The EXPLAIN statement is only relevant for simple queries and has limited impact on optimization.

The EXPLAIN statement is used to retrieve data from multiple tables but does not affect query performance.

3. Discuss the concept of database denormalization and situations where it might be considered beneficial.

Denormalization involves intentionally introducing redundancy in a database to improve query performance. It may be considered beneficial in scenarios with complex queries and read-heavy workloads.

Denormalization is always detrimental to database performance and should be avoided.

Denormalization is only suitable for write-heavy workloads and has no impact on query performance.

Denormalization is a technique to remove all redundancy from a database, improving overall performance.

4. In the context of databases, what is a subquery?

A precompiled collection of one or more SQL statements

An event that automatically invokes an action

A query nested within another query

An index created on a specific column

5. What does the term 'Normalization' refer to in the context of databases?

Optimizing query performance

Reducing redundancy and dependency

Increasing data redundancy

Enhancing data encryption

6. Which type of relationship is represented by a foreign key in a database?

One-to-Many

Many-to-Many

One-to-One

None of the above

7. What is the purpose of the COMMIT statement in SQL?

To filter rows based on a condition

To undo changes made during the current transaction

To commit changes made during the current transaction

To sort the result set

8. What is the purpose of the CASE statement in SQL?

To filter rows based on a condition

To perform conditional logic in a SELECT statement

To sort the result set

To group rows based on a condition

9. Which SQL statement is used to revoke previously granted privileges on a database object?

REVOKE

DENY

REMOVE PRIVILEGES

DISALLOW ACCESS

10. What is the purpose of the HAVING clause in SQL?

To filter rows based on a condition

To sort the result set

To group rows based on a condition

To filter the result set after grouping

11. What does the term 'Index' refer to in the context of databases?

A group of related data

A collection of SQL statements

An ordered list of values with corresponding row locations

A constraint that ensures data integrity

12. What does CRUD stand for in the context of databases?

Create, Retrieve, Update, Delete

Compile, Run, Update, Debug

Copy, Remove, Undo, Delete

Categorize, Revert, Update, Debug

13. In database terms, what does ACID stand for?

All Columns Indexed and Defined

Atomicity, Consistency, Isolation, Durability

Advanced Constraints and Index Definitions

Aggregate, Combine, Insert, Delete

14. Examine the role of stored procedures in a database and provide examples of situations where they offer advantages.

Stored procedures are precompiled sets of one or more SQL statements stored in a database. They offer advantages such as improved performance, reduced network traffic, and enhanced security.

Stored procedures are only useful for simple queries and have no impact on performance in a database.

Stored procedures increase network traffic and introduce security risks in a database.

Stored procedures are useful for data encryption but have no impact on query performance.

15. Which SQL statement is used to add a new column to an existing table?

ADD COLUMN

ALTER TABLE

INSERT INTO

CREATE COLUMN

16. Explain the concept of database normalization and its importance in database design.

Normalization is the process of reducing data redundancy and dependency in a database. It ensures efficient storage and avoids update anomalies.

Normalization involves adding redundancy to improve query performance in a database. It is not crucial for database design.

Normalization is a technique to increase data redundancy for faster retrieval.

Normalization is the process of creating duplicate data for backup purposes in a database.

17. What is the purpose of the ORDER BY clause in SQL?

To filter rows based on a condition

To sort the result set

To group rows based on a condition

To perform mathematical calculations on numeric columns

18. Which SQL statement is used to add new data to a database?

INSERT INTO

CREATE

ADD

NEW DATA

19. What is the purpose of the COALESCE function in SQL?

To filter rows based on a condition

To perform conditional logic in a SELECT statement

To return the first non-null expression in a list

To group rows based on a condition

20. What does SQL stand for in the context of databases?

Structured Query Language

System Query Language

Sequential Query Language

Standardized Query Language

RDBMS MCQ Test 4