Pessimistic Concurrency
Pessimistic concurrency is a database and system design approach that assumes conflicts between concurrent transactions are likely, so it prevents them by locking resources. It involves acquiring locks (e.g., read or write locks) on data before performing operations, ensuring exclusive access until the transaction completes. This method prioritizes data consistency and integrity over performance in multi-user environments.
Developers should use pessimistic concurrency in scenarios where data integrity is critical and conflicts are frequent, such as financial systems, inventory management, or booking applications where concurrent updates could lead to inconsistencies. It's ideal when transactions are long-running or when the cost of rolling back a transaction due to a conflict is high, as it prevents conflicts proactively rather than detecting them after they occur.