What is a Source key?
In Sources, we ask you to select what column is the Source key.
The Source key is the way the external system you plugged as a Source uniquely identifies a record (Salesforce Id, Hubspot Id, email in Intercom & Sendinblue...).
While we can try to automatically detect it if you use one of our SaaS connections, we can’t always do the same if you are importing data from a database or an SFTP (we don’t know what system this data is originally coming from).
Selecting the Source key is extremely important to make sure we always deliver the most recent version of each record to the Dataset (that’s why we also ask you which column states when a record has been updated).