RDS restore native backup and lazy loading from S3

Hello,

If you access data that hasn't been loaded yet, the DB instance immediately downloads the requested data from Amazon S3, and then continues loading the rest of the data in the background.

On tables to which you require quick access, you can perform operations that involve full-table scans, such as SELECT * . This will allow Amazon RDS to download all of the backed-up table data from S3.

Further more, all data is lazy loaded to the DB instance when you restore from a snapshot, the key difference is when you need quick access to the data that hasn't been loaded to the DB instance yet. In this situation, the DB instance will pull the data needed from S3 and make it available instantly without lazy loading.

Additional information about Restoring a DB Snapshot can be found in this AWS Documentation. I'd also advise you to check the Limitations and recommendations for importing backup files from Amazon S3 to Amazon RDS.

And one of them states that,

Importing from Amazon S3 is not supported on the db.t2.micro DB instance class. However, you can restore to a different DB instance class, and change the DB instance class later.

I hope this helps.