Fivetran offers an efficient method for keeping databases in sync with data warehouses through log-based replication. This technique reads the logs of changes to the master database, using less computing power compared to alternative methods such as "last modified queries" and "daily snapshots." Log-based replication captures deleted information and does not compete with other database queries, providing real-time updates. The approach helps businesses avoid potential performance issues during peak times like Black Friday. Fivetran supports three column-oriented warehouses: Google BigQuery, Amazon Redshift, and Snowflake.