Keep N Checkpoints
The easiest way to manage checkpoints and their associated files is to decide how many checkpoints you want to be referenced in the database configuration file (so that you can restore the database directly from files on disk or from files restored from backup).
To keep n checkpoints
Add the following command after your routine checkpoint command:
alterdb dbname -keep=n
The specified number of latest valid checkpoints is preserved and all older checkpoints are deleted.
This command is sufficient for most purposes. Occasionally, however, you may need other commands, described next.