From: László Tibor <ltibor@mail.tiszanet.hu>
To: pgsql-odbc <pgsql-odbc@postgresql.org>
Subject: RE: [INTERFACES] 7.1 beta 3 Linux ODBC BEGIN Behaviour
Date: Sat, 10 Feb 2001 19:15:56 +0100
Message-ID: <NEBBJDDFALKDHFBLCGCPIEBFCAAA.ltibor@mail.tiszanet.hu> (raw)
In-Reply-To: <3976.981826245@sss.pgh.pa.us>
> It'd be nice if ODBC could distinguish SELECT FOR UPDATE from plain
> SELECT, but in practice it cannot reliably do so. Doubtless we could
> extend ODBC to look for "FOR UPDATE" in the text of the query, but
> that will only catch simple situations. Consider these possibilities:
>
> * A view or rule invoked by the query uses FOR UPDATE. (Pre-7.1, we
> didn't support FOR UPDATE in views ... but we do now.)
>
> * A function invoked by the query does SELECT FOR UPDATE internally.
>
> For that matter, it's quite possible for a function invoked by a SELECT
> to do INSERT/UPDATE/DELETE internally. Therefore, it's impossible for
> the ODBC driver to reliably distinguish a pure SELECT from a SELECT that
> causes locking or even data updates.
>
> Given these considerations, I think it's a mistake for ODBC to treat
> SELECT differently from other queries for the purpose of setting
> transaction boundaries.
>
> regards, tom lane
Thank you Tom. I agree. Regards, Tibor
Tibor Laszlo
ltibor@mail.tiszanet.hu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-interfaces@postgresql.org
Cc: ltibor@mail.tiszanet.hu, pgsql-odbc@postgresql.org
Subject: RE: [INTERFACES] 7.1 beta 3 Linux ODBC BEGIN Behaviour
In-Reply-To: <NEBBJDDFALKDHFBLCGCPIEBFCAAA.ltibor@mail.tiszanet.hu>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox