ADR has a retention policy, controlled by the short and long purge policies in ADR_CONTROL. These policies determine how long incidents, trace files, and related diagnostic data are kept before purge.

Why this is yes: Oracle ADR is designed to retain diagnostic data only for a defined period, and automatic purge is handled by MMON when configured and working correctly.

Effect: older incidents and files are removed automatically, reducing ADR growth and keeping diagnostic storage under control. If purge is not working, ADR can continue to grow and stale health-monitor or incident data may remain.

Steps:

1. Check ADR_CONTROL with adrci.
2. Review SHORTP_POLICY and LONGP_POLICY.
3. Adjust them to a suitable retention period if needed.
4. Verify automatic purge is functioning, or purge manually if necessary.