On Mon, Oct 4, 2021 at 1:48 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> My mental model of these things is that the target table is cross-joined
> to the additional tables as though by a comma in FROM [...]
Mine as well.
I just managed to dredge up some history here though. Turns out you
explicitly disabled this feature for 9.4 to make room for a future
feature to allow left-joining the target table [0]. Is support for
that feature still desired/planned? (If it's been permanently
abandoned for whatever reason, then maybe it's safe just to revert
158b7fa?)
[0]: https://github.com/postgres/postgres/commit/158b7fa6a34006bdc70b515e14e120d3e896589b
Nikhil
