Message-ID: <4AF2C066.7070201@postnewspapers.com.au>
Date: Thu, 05 Nov 2009 20:09:10 +0800
From: Craig Ringer <craig@postnewspapers.com.au>
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To: Eduardo Morras <emorras@s21sec.com>
CC: pgsql-performance <pgsql-performance@postgresql.org>
Subject: Re: Followup: vacuum'ing toast
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	<4AF24006.1010509@postnewspapers.com.au>
	<20091105090655.8EA085580B0@s21sec.com>
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Craig Ringer wrote:
> Eduardo Morras wrote:
>>> 3) Autocommit being disabled. At least when using Hibernate via JPA,
>>> that'll cause a major mess and would easily explain the issues you're
>>> seeing. Hibernate manages transactions explicitly when required, and
>>> expects autocommit to be off.
>> Excuse me but i don't understand this point. You say that the problem happens if Autocommit is disabled but that hibernates expects that Autocommit is disabled for a correct work. What's better then? Autocommit off for Hibernate or Autocommit On for the original poster problem. Can you explain it more?
> 
> Argh!
> 
> I'm really sorry. I meant that Hibernate expects autocommit to be
> _enabled_.

Some searching suggests that, indeed, the issue is that when using
Hibernate via JPA (Hibernate EntityManager) autocommit needs to be left
enabled.

For some reason there doesn't seem to be any explicit reference to
autocommit in the Hibernate EntityManager docs or the EJB3 spec. I can't
find anything but (numerous) forum posts and the like on this, so don't
take it as definitive.

--
Craig Ringer