How should the job handle updates to data over time?

Using this option you truncate (delete all existing records) the target table every time, before inserting the records from the source table.

Use a primary key column to look up if a record already has been copied or not. If the record exists in the target already, issue an UPDATE instead of an INSERT.

Primary key column:

Do not handle update logic in the job / handled elsewhere (running the job several times may cause duplicates).