Select the option that is not true. 1. Timestamp and Validation schedulers are both optimistic schedulers. 2. Timestamp and Validation schedulers can be used to remove physically unrealizable behaviour. 3. Timestamp and Validation schedulers guarantee serializability. 4. Timestamp and Validation schedulers perform most effectively on transactions that perform writes.

Respuesta :

Answer:

3. Timestamp and Validation schedulers guarantee serializability.

Explanation:

Timestamp is a sequence of information encoded when a certain event occurs at a given time that information is decoded and message is identified. Time schedulers is optimistic scheduler and it removes physically unrealizable behavior. Timestamp cannot guarantee serializability.  It can detect unrealizable behavior.