How Oracle Handles Concurrency Control and Ensures Data Consistency in a Multi-user Environment

Oracle uses a variety of mechanisms to handle concurrency control and ensure data consistency in a multi-user environment. These mechanisms include:

• Locking: Oracle uses locks to control access to data and prevent multiple users from modifying the same data simultaneously. This helps in maintaining data consistency by ensuring that only one user can modify a data at a time.
• Isolation levels: Oracle offers different isolation levels such as READ COMMITTED and SERIALIZABLE to control the visibility of changes made by one user to others. This helps in preventing dirty reads and ensuring data consistency.
• Transactions: Oracle uses transactions to group multiple database operations into a single, atomic unit. This ensures that either all operations in a transaction are completed successfully or none of them are applied, thus maintaining data consistency.

By utilizing these mechanisms, Oracle effectively handles concurrency control and ensures data consistency in a multi-user environment.