Which two statements are true about checkpointing? (Choose two.)
A.
The checkpoint frequency decreases with the smaller redo log file size.
B.
It ensures that all committed data is written to the data files during normal shutdown.
C.
The frequent full checkpoint in a database can cause the overall degradation of the database
performance.
D.
It prompts the Checkpoint (CKPT) process to write data to the data files and redo information to
the online redo log files.
Explanation:
Checkpoint Process (CKPT)
A checkpoint is a data structure that defines a system change number (SCN) in the redo thread of
a database. Checkpoints are recorded in the control file and in each data file header. They are a
crucia element of recovery.
When a checkpoint occurs, Oracle Database must update the headers of all data files to record
the details of the checkpoint. This is done by the CKPT process. The CKPT process does not write
blocks to disk; DBWw always performs that work. The SCNs recorded in the file headers
guarantee that all changes made to database blocks prior to that SCN have been written to disk.
The statistic DDWR checkpoints displayed by the SYSTEM_STATISTICS monitor in Oracle
Enterprise Manager indicate the number of checkpoint requests that have completed.
