[discretion22]

That sounds very close to NATURAL JOIN which is already present[0] although that does rely on the typical convention of FK columns being named the same on parent and child (related) tables.

I think you are suggesting some sort of lookup based on the defined FK relation, but that would be confused by situations where tables have multiple FK relations, such as tables with values restricted by a lookup value table (or more than 1 such FK). Those are pretty common, so I could see the 'AUTO' feature breaking down quickly. I think that is why the NATURAL JOIN approach is taken and that basically does what I believe you are describing, provided the column naming is matched.

[0] https://www.postgresql.org/docs/15/queries-table-expressions...

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