We previously only allowed External ID as a valid field for Primary Key in the Salesforce bulk upsert action. We now accept all indexed fields (Salesforce record ID, Name, any custom indexed field) as well.
Use cases
For customers that do not store an ID in their external systems and use the Salesforce record ID (or other internal fields) as the primary identifier of a record, they can now use that field as the Primary Key by toggling the field to text and entering the name of the field.
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