A Level Computer Science OCR Practice Exam

What is the main purpose of record locking in a database?

1. To delete unwanted records

2. To allow faster data access

3. To prevent data inconsistencies caused by simultaneous access

4. To enhance data storage capacity

The correct answer is: To prevent data inconsistencies caused by simultaneous access

The primary purpose of record locking in a database is to prevent data inconsistencies that can occur when multiple users or processes try to access and modify the same piece of data simultaneously. When a record is locked, it ensures that only one transaction can make changes to that record at a time. This mechanism helps maintain data integrity and consistency, as it prevents scenarios where one user might overwrite changes made by another user before their transaction is completed. For example, if two users attempt to edit the same record at the same time, without locking, the first user's changes could be unintentionally lost when the second user's changes are saved. By implementing record locking, the database ensures that all modifications are executed in a controlled manner, preserving the accuracy of the data. The other options focus on different aspects of database functionalities. Deleting unwanted records is not related to the purpose of locking, and while faster data access may be a beneficial effect of good database design, it is not the primary goal of record locking. Additionally, enhancing data storage capacity pertains to how data is managed and stored rather than how data is accessed or modified concurrently.