Select all statements that are true regarding database checkpoints:

Group of answer choices

A checkpoint operation is recorded in the transaction log

Database checkpoints are operations in which the DBMS writes all updated $($dirty$)$ block buffers in the RAM block buffer cache to durable storage. This enables recovery of the database state at the time of the checkpoint from disk or other storage

Checkpoints play a key role in defending databases from denial of service attacks

Checkpoints play an important role in transaction recovery

Checkpoints must be scheduled by an administrator to assure database recoverability