@jenibelle08 You save my life!
I used Digital Ocean to serve my Strapi 4. It is upgraded to managed Database cluster.
The point you mentioned, “db”, is the “db” tab in the components of the App.
I was trapped while I try to restore my DB from a backup
When try to restore the DB,
Digital Ocean will create a new Database cluster from the backup.
After the new cluster is created, we have to attach the new DB cluster to the Strapi App.
And cancel the auto build immediately.
Then update all the environment variables as you said, to the ${xxxx.HOSTNAME} , where xxxx is the new DB cluster component name I want to attach to my strapi.
app-YYYY is the unique ID of the cluster component
Save and Let it build once.