Best practices for application availability during maintenance

Autonomous Database patches are applied during a scheduled maintenance window as rolling patches.

Using rolling patches, your Autonomous Database instance is made available on new cluster nodes before patching starts on the original nodes where it was running.

After the database is available on new cluster nodes, all new connections are directed to the new nodes. This means the database remains online and available during maintenance and new database connection requests will succeed during the maintenance window.

See Best Practices to Maintain Application Availability During Maintenance Windows for more information.