What isolation level should be chosen to prevent overbooking only through the isolation level?

To prevent overbooking, the transaction isolation level is usually set to Serializable. This level provides complete isolation of transactions, ensuring that concurrent execution is equivalent to sequential execution. As a result, anomalies such as phantom reads and unpredictable updates, which can lead to overbooking, are eliminated.

For example, when booking tickets, multiple transactions cannot read the available seats and book them simultaneously because Serializable locks conflicting operations, ensuring data consistency.

However, it is important to consider that the Serializable level may reduce performance due to locking and waiting, so additional mechanisms such as optimistic locking or version control are sometimes used.