From: Hiroshi Inoue <Inoue@tpf.co.jp>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Hiroki Kataoka <kataoka@interwiz.koganei.tokyo.jp>
Cc: pgsql-interfaces@postgresql.org
Cc: pgsql-odbc@postgresql.org
Cc: Steve Wranovsky <stevew@merge.com>
Subject: RE: 7.1 beta 3 Linux ODBC BEGIN Behaviour
Date: Sun, 11 Feb 2001 06:37:02 +0900
Message-ID: <EKEJJICOHDIEMGPNIFIJCEBDDJAA.Inoue@tpf.co.jp> (raw)
In-Reply-To: <3976.981826245@sss.pgh.pa.us>
> -----Original Message-----
> From: Tom Lane
>
> 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.
>
OK, agreed.
However simply putting back the behabior make it impossible to call
VACUUM in psqlodbc autocommit off mode.
My idea is as follows.
[In autocommit off mode]
1) All statements except STMT_TYPE_OTHER issue
"BEGIN" if a trasaction isn't in progress.
2) STMT_TYPE_OTHER statements automatically issue
"COMMIT" if a transaction is progress.
Comments ?
Regards,
Hiroshi Inoue
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To: pgsql-interfaces@postgresql.org
Cc: Inoue@tpf.co.jp, tgl@sss.pgh.pa.us, kataoka@interwiz.koganei.tokyo.jp, pgsql-odbc@postgresql.org, stevew@merge.com
Subject: RE: 7.1 beta 3 Linux ODBC BEGIN Behaviour
In-Reply-To: <EKEJJICOHDIEMGPNIFIJCEBDDJAA.Inoue@tpf.co.jp>
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