From: Bruce Momjian <pgman@candle.pha.pa.us>
Message-Id: <200102071912.OAA27530@candle.pha.pa.us>
Subject: PostgreSQL and PHP persistent connections
To: "Thies C. Arntzen" <thies@digicol.de>
Date: Wed, 7 Feb 2001 14:12:26 -0500 (EST)
CC: Rasmus@candle.pha.pa.us, Lerdorf <rasmus@php.net>,
	PostgreSQL-interfaces <pgsql-interfaces@postgresql.org>
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Thies, we talked at LinuxWorld about improving the reliability of
persistent PostgreSQL connections in PHP.

I believe the problem is that persistent connections sometime do not
pass clean sessions because of open transactions and SET changes to the
session.

We discussed using 'ROLLBACK' before passing a connection to a new user,
but the problem was that ROLLBACK with no open transaction causes a
server log error message.  We discussed adding 'ROLLBACK SILENT' to fix
this, but I believe a better, more portable solution is a simple "BEGIN
WORK;ROLLBACK".  This will do nothing if there is no open transaction,
and will ROLLBACK any open transaction.  I propose this be sent by PHP
as the first query when passing persistent connections.

As far as SET changes, does anyone on the PostgreSQL interfaces list
have a suggestion on how to RESET all session parameters?  Seems we may
need to add this feature in to the backend.

-- 
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