Skip site navigation (1) Skip section navigation (2)

Re: Allow pooled connections to list all prepared queries

From: Kris Jurka <books(at)ejurka(dot)com>
To: David Brown <dave(at)spoonguard(dot)org>
Cc: PostgreSQL Global Development Group <pgsql-patches(at)postgresql(dot)org>,Charlie Peck <charliep(at)cs(dot)earlham(dot)edu>
Subject: Re: Allow pooled connections to list all prepared queries
Date: 2004-12-27 18:03:08
Message-ID: Pine.BSO.4.56.0412271253540.992@leary.csoft.net (view raw or flat)
Thread:
Lists: pgsql-patches

On Sat, 25 Dec 2004, David Brown wrote:

> You're right, in the case of standalone Perl or Apache::DBI. However, if 
> DBD::Pg happens to grab an already-open connection that doesn't have a 
> one-to-one correspondence with a $dbh (e.g. from a Postgres connection pool, 
> or from an external pooling server like DBBalancer[1]), the state of the 
> connection (with respect to past PREPAREs) isn't known.
> 

I'm not clear why the pooling case is different.  Speaking from the JDBC 
side (which does connection pooling, but not statement pooling) there is 
a proxy connection object which wraps a real connection.  So each new 
connection from the pool gets a new proxy object, but the real underlying 
connection stays the same.  So the real connection will know what it has 
or has not prepared.  So I don't see why, simply because it's in a pool, 
that it forgets what's been prepared.

Kris Jurka

In response to

Responses

pgsql-patches by date

Next:From: David BrownDate: 2004-12-27 19:12:20
Subject: Re: Allow pooled connections to list all prepared queries
Previous:From: Hans-Juergen SchoenigDate: 2004-12-27 10:31:53
Subject: Implementing SELECT FOR UPDATE [NOWAIT]

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group