Relationship() in Salesforce Adaptor

I’m sure there is a very simple answer to this, but I can’t seem to get it. I am trying to add a relationship function to a job, and I want to use the Salesforce ID as my external ID. However, I am getting “Field name provided, Id is not an External ID or indexed field” as an error. Can we not use the Salesforce ID as our external ID field in the relationship function?

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In that case just use field(…). Relationship is effectively a lookup helper if you need to match on something other than the Id.