Re: postgres fe/be protocol

----- Original Message -----
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Chris Bitmead <chris@bitmead.com>
Cc: Postgres Hackers List <hackers@postgresql.org>
Sent: Monday, July 10, 2000 4:44 PM
Subject: Re: [HACKERS] postgres fe/be protocol


> Chris Bitmead <chris@bitmead.com> writes:
> > I inserted some debug into libpq, then I ran psql, and I noticed that
> > there are two 'Z' "Ready for query" messages sent after each query. Is
> > there a reason for that? Is it a bug?
>
> I'm pretty sure the backend sends only one 'Z' per query cycle.  Are you
> watching the outgoing requests too?  Maybe psql is sending an extra
> empty query.  (It didn't use to do that, but maybe it does after Peter's
> recent work on it...)

Actually it used to when it first made a connection to test that it was
alive, but not afterwards. JDBC was originally based on libpq, but I
replaced the empty query with a couple of useful ones.

>
> regards, tom lane