To delete an instance:
Console
- Go to the Cloud SQL Instances page in the Google Cloud Platform Console.
- Select an instance to delete by clicking the instance name.
- Click Delete.
- In the Delete database instance dialog box, click OK.
gcloud
Delete the instance.
gcloud sql instances delete [INSTANCE_NAME]
Notes:
- You cannot delete an instance that has any replicas. You must delete all replicas first.
After you delete an instance, it might still appear in your project with an "unknown" size but with a "Being deleted" status. This is normal and the instance should disappear completely after a brief period of time.
You cannot reuse an instance name for up to a week after you have deleted an instance.