Oracle performs the maintenance of the DB system that starts within two hours of the Maintenance window start time that you define for the DB system. The maintenance is performed monthly.

If you do not define the Maintenance window start time, Oracle defines one for you. It is recommended to confirm that the automatically selected window suits your timings. While the maintenance is going on, the DB system status changes to UPDATING and the DB system is unavailable for a short time. During this time, MySQL HeatWave Service does not monitor the metrics.

You have to manually update the release versions of the MySQL server, such as from version 8.0.27 to 8.0.28. See MySQL Server Upgrades.

After the maintenance is complete, the DB system is returned to the pre-maintenance state. If the DB system is in the INACTIVE state when the maintenance starts, it is returned to the INACTIVE state after the maintenance completes.