On Wed, 2021-05-19 at 15:45 +0000, Godfrin, Philippe E wrote: > From: Laurenz Albe <laurenz.albe@xxxxxxxxxxx> > >On Tue, 2021-05-18 at 16:13 +0000, Godfrin, Philippe E wrote: > > > That seems very promising, though I’m not certain how I’d code that in the create > > > foreign server syntax. My testbed is not quire ready right now, so I’ll ask instead of testing. > > > Is this what you mean: > > > > > > CREATE SERVER FDW001 FOREIGN DATA WRAPPER POSTGES_FDW > > > OPTIONS (HOST ‘FOORW, FOORO’, DBNAME ‘FOODB,FOODB’, PORT ‘5432,6432’, > > > TARGET_SESSION_ATTRS ‘ANY,READ-ONLY’ > > > > Pretty much, yes. Except you can only specify a single setting for > > "target_session_attrs". > > OK – so using target_session_attr=’read-write’ will use the show transaction_read_only > command – if the reply is ‘on’ the connection is closed, which will then go to the next > host/port combination… > Seems to me, then, it’s the libpq operation that permits the selection… Yes, the postgres_fdw options are mostly libpq connection parameters. > Hmm, wait a minute. Then how do you segregate connections by RO ?? I can’t wait until v14 Right. If you cannot wait for v14, that is hard luck. You could use a load balancer, perhaps that can be configured to check "pg_is_in_recovery()". Yours, Laurenz Albe -- Cybertec | https://www.cybertec-postgresql.com
