How to delete a Managed Database Instance
Click Database on the left side menu. A list of your Database Instances displays.
Click the Database name or «See more Icon» > More info to access the Database information page.
Scroll down the page to the Delete Instance section and click Delete Instance. A pop-up appears to inform that:Important:
This will permanently destroy your Instance and all your data will be lost. This action is irreversible.
Type DELETE to confirm and click Delete this Instance.
Alternatively, you can delete your Instance from your Database Instances list by clicking «See more Icon» next to the Instance name and then Delete.