How to reduce Google Cloud SQL instance size?

Solution 1:

As it is indicated in the official documentation, it is not possible to reduce the storage capacity of a Cloud SQL instance. You can give more capacity to an instance if needed, but the change is permanent and cannot be rolled back.

The best option for you right now would be to create a SQL dump file and export your current data into it. Then, in a new Cloud SQL instance with the desired capacity, import the SQL dump file so that all your data is stored in the new instance. To reduce time and costs for this process, please follow these best practices, including the use of the appropriate flags, compressing your data and other tips available for faster and less expensive imports and exports.

However, the possibility of reducing the capacity of a Cloud SQL instance has been requested as a new feature and is currently being worked on. Head to the link and click on the star icon on the top left corner to get email notifications on any progress made on this request.