> Also, IN (subquery) is a known performance problem in PGSQL, at least if
the subquery is going to return > many rows.
> It's too bad, since I'm rather fond of subqueries, but I avoid them like
the plague in PostgreSQL.
You're not really using a subquery - really just a long list of integers.
Subqueries are lightning fast, so long as you conver to the EXISTS form:
SELECT * FROM tab WHERE id IN (SELECT id2 FROM tab2);
SELECT * FROM tab WHERE EXISTS (SELECT id2 FROM tab2 WHERE id2=id);
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