Choose a migration method

Which method you choose depends on your database size, network upload and download speeds, existing continuous aggregates, and tolerance for failure recovery.

If you are migrating from an Amazon RDS service, Amazon charges for the amount of data transferred out of the service. You could be charged by Amazon for all data egressed, even if the migration fails.

If your database is smaller than 100 GB, choose to migrate your entire database at once. You can also migrate larger databases using this method, but the copying process must keep running, potentially over days or weeks. If the copy is interrupted, the process needs to be restarted. If you think an interruption in the copy is possible, choose to migrate your schema and data separately instead.

Migrating your schema and data separately does not retain continuous aggregates calculated using already-deleted data. For example, if you delete raw data after a month but retain downsampled data in a continuous aggregate for a year, the continuous aggregate loses any data older than a month upon migration. If you must keep continuous aggregates calculated using deleted data, migrate your entire database at once regardless of database size.

If you aren't sure which method to use, try copying the entire database at once to estimate the time required. If the time estimate is very long, stop the migration and switch to the other method.