On Mon, 23 Feb 2026 at 21:21, Peter Eisentraut <peter(at)eisentraut(dot)org> wrote:
> I read in the SQL standard that SELECT * in EXISTS is not supposed to be
> expanded to all columns, but only to an arbitrary literal. This
> corresponds to the recommendation in the PostgreSQL documentation to
> write EXISTS (SELECT 1 ...) instead. But not even our own tests and
> example code use that latter convention consistently, so I think many
> users don't know it or observe it either. So implementing that little
> optimization for SELECT * seems reasonable.
> Thoughts?
Don't we already do this in simplify_EXISTS_query()?
David