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Summary

Bracket uses Notion object IDs provided through the NOtion API to uniquely map each record to the opposing data source. The user does not need to do any prep work to configure primary keys.

If you would like to sync the Notion record ID to a field in the opposing data sources, just add a formula field in your Notion database with the formula id(), and add the field to the field mapping on the Bracket webapp.
ConnectingDynamoDB