Reverse ETL Sync Modes

The Reverse ETL sources support two sync modes that you can configure while connecting them to a destination. These modes define how RudderStack syncs your data to the destination:

• Upsert mode
• Mirror mode

The following sources support these sync modes:

• BigQuery
• Databricks
• MySQL
• PostgreSQL
• Redshift
• Snowflake
• Trino

When you sync data from these source for the first time, RudderStack performs a full sync by default, irrespective of the sync mode. It then incrementally syncs any new data since the last sync. However, you can force a full data sync using the Force Full Resync option.

Upsert mode

In this mode, RudderStack supports insertion of new records and updates to the existing records while syncing data to the destination.

Whenever you update the column mappings, RudderStack runs a full sync the next time.

Supported destinations

RudderStack supports upsert mode for all destinations except the destinations that support only mirror mode.

Mirror mode

In this mode, RudderStack ‘mirrors’ the source by keeping the destination data the same as the source data. It performs insertion, updates, and deletion of records while syncing data to the destination.

RudderStack does not support track event type for this mode.

Supported destinations

RudderStack supports mirror mode for the following destinations:

Whenever you update the column mappings, RudderStack runs a full sync the next time. While performing a full sync, RudderStack first deletes all existing records and then syncs the records as per the latest column mappings.

FAQ

What happens to the records that have not been successfully sent to the destination in the previous sync?

In case of an unsuccessful delivery, RudderStack retries sending the events in the next sync.

Questions? Contact us by email or on Slack