On 2013-12-05 23:01:28 +0200, Heikki Linnakangas wrote: > On 12/05/2013 10:37 PM, Robert Haas wrote: > >On Thu, Dec 5, 2013 at 3:05 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > >>It might be unpleasant to use in some cases, though. > > > >Why would there be more than a few cases in the first place? Who is > >going to use this beyond psql, pg_dump(all), and pg_upgrade, and why? > > Well, you might want to use pgAdmin, or your other favorite admin tool. I'm > not sure how well it would work, and I think it's OK if we say "sorry, can't > do that", but it's not a crazy thing to want.
Pgadmin wouldn't work, it uses multiple connections for anything but the most trivial tasks. You can't even send a manual sql query using only one connection. I think that's true for most of the non-trivial tools. > >>Another issue is that we have too many variants of PQconnect > >>already; which of them are we prepared to clone for this > >>hypothetical new connection method? > > > >PQconnectdbParams, I assume. Isn't that the one to rule them all, > >modulo async connect which I can't think is relevant here? > Right. Not all of the parameters will make sense for a stand-alone backend > though, like the hostname and port number. And I think you need need a new > parameter to pass the path to the 'postgres' executable, unless we re-use > the host parameter for that. Hm. I'd guessed that we wouldn't use the connection string to pass down the executable name and the datadir now that we're inventing a separate function. But maybe that's unneccessary. What parameters do we require to be set for that mode: * path to postgres * data directory * database name (single mode after all) * port, because of the shmem key? I'd say that's not important enough I think we also need to be able to pass some additional parameters to postgres: - config_file, hba_file, ... might be required to start pg in some environments - -P, -O , are sometimes required in cases single user mode is neccessary for data recovery. So I think we should just allow passing through arguments to postgres. Not sure if we need anything but the pid of the postmaster be returned? > >Or don't clone that one but instead have > >PQnextConnectionShouldForkThisBinary('...') and let the psql/pg_dump > >switch be --standalone=full-path-to-the-postgres-binary. Yuck, that's ugly. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers