Sender: wn@kja-essen.de
Message-ID: <37F62682.D3A869EA@kja-essen.de>
Date: Sat, 02 Oct 1999 17:36:34 +0200
From: Wolfgang Hottgenroth <wn@kja-essen.de>
Reply-To: woho@ieee.org
MIME-Version: 1.0
To: Tom Lane <tgl@sss.pgh.pa.us>
CC: woho@ieee.org, pgsql-interfaces@hub.org
Subject: Re: [INTERFACES] problems with large-objects
References: <1665.938878406@sss.pgh.pa.us>
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Hi Tom,


thank you for that fast answer. So I failed when reading the manual,
because I never realized, that using transactions are a requirement when
working with LO's.

Wolfgang


Tom Lane wrote:
> 
> Wolfgang Hottgenroth <wn@kja-essen.de> writes:
> > Sometimes ago I want to switch from 6.4.2 to 6.5.1 and my tools, using
> > the large objects through the perl-library refused to work. lo_import
> > didn't work anymore.
> 
> 6.5.* only allows large objects to be kept open within a single
> transaction; you have to wrap BEGIN...END around anything that involves
> lo_open ... lo_read/write ... lo_close.  In particular, since lo_import
> and lo_export are just such sequences, they need to be called inside
> a transaction.
> 
> This restriction has been documented as required all along, but older
> Postgres releases didn't enforce it (they'd just fail once in a while
> if you didn't do it :-().
> 
> It'd be nice if lo_import could start/finish a transaction for itself,
> but I don't see any good way to do that without breaking things for
> the case that you want to do several lo_imports in one transaction.
> 
>                         regards, tom lane