Re: commit problems

This is an OpenPGP/MIME signed message (RFC 2440 and 3156)
--===============4899666762666875320==
Content-Type: multipart/signed; micalg=pgp-sha1;
 protocol="application/pgp-signature";
 boundary="------------enig092C8ACC4917AFCF7C845A20"

This is an OpenPGP/MIME signed message (RFC 2440 and 3156)
--------------enig092C8ACC4917AFCF7C845A20
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

On 08/23/10 16:55, Richard Harley wrote:
> We have had a problem with postgresql 8.3 on a Windows server 2008. I
> wonder whether there has been any other experiences like this. We have
> connected to Potsgres from Zope via a Psycopg adapter and noticed that
> sometimes when data is inserted via a form in Zope, the data is
> available in Zope but doesn't get committed to the database. This has
> come to a head over the weekend where at least one month's worth of dat=
a
> has disappeared and this includes changes to the actual database
> structure - luckily only on a testing machine, but concerning neverthel=
ess.
> The data seemed to disappear after we upgraded to the most recent
> version of Zpsycopg2 database adapter, previously we were using version=

> 1 (I know it's old, we are only testing after all) and have never had
> these sorts of problem before. It's almost as if all the data and
> changes to the db were held in memory, and Postgres continued to work
> fine from there, but when the db adapter was changed and Zope restarted=

> everything was cleared from memory.
> Has anyone had similar experinces or can anyone cast any light on where=

> the problem may lie. To us it seems the db adapter is the most likely
> candidate but we can't understand how this could happen, explanations
> also welcome.

What you describe, PostgreSQL keeping 1 month worth of changes to the
database schema "in memory" and then loosing everything can happen only
if you have a single transaction 1 month long and sincerely I don't see
how this is possible. Also, from what I know Zope doesn't cache the
results of an ALTER, INSERT or any other non-SELECT query so, again, I
can't see how what you describe can happen. If you insert some data and
in a successive request the data is there then an explicit delete (or
DROP/CREATE TABLE) is required to remove it.

This seems like a bug in your application to me.

federico

--=20
Federico Di Gregorio                                       fog-NGVKUo/i/[email protected]
 In some countries (e.g., Germany) even many brands of toilet paper have
  format A6.             [http://www.cl.cam.ac.uk/~mgk25/iso-paper.html]


--------------enig092C8ACC4917AFCF7C845A20
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: OpenPGP digital signature
Content-Disposition: attachment; filename="signature.asc"

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.10 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iEYEARECAAYFAkxynaIACgkQvcCgrgZGjevm3ACeM+VNZjrB/fE09JAbQHDrgRFB
r/YAoMHoB78h/2W+Qk3YyUbiUtHMbjlb
=fzTj
-----END PGP SIGNATURE-----

--------------enig092C8ACC4917AFCF7C845A20--

--===============4899666762666875320==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________
Psycopg mailing list
Psycopg-IAPFreCvJWPBWskQ1e/[email protected]
http://lists.initd.org/mailman/listinfo/psycopg

--===============4899666762666875320==--