Re: [NOVICE] Last ID Problem - Mailing list pgsql-hackers

From Mark Cave-Ayland
Subject Re: [NOVICE] Last ID Problem
Date
Msg-id 9EB50F1A91413F4FA63019487FCD251DADF7@WEBBASEDDC.webbasedltd.local
Whole thread Raw
In response to Re: [NOVICE] Last ID Problem  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Hi Tom,

> -----Original Message-----
> From: Tom Lane [mailto:tgl@sss.pgh.pa.us]
> Sent: 02 February 2005 15:35
> To: Mark Cave-Ayland
> Cc: 'Alvaro Herrera'; 'Michael Fuhr'; 'Mitch Pirtle'; 'Tatsuo
> Ishii'; pgsql-hackers@postgresql.org; operationsengineer1@yahoo.com
> Subject: Re: [NOVICE] Last ID Problem

(cut)

> No.  The thing everyone is ignoring here is that the INSERT
> command tag format is not something we can just go and
> change.  You certainly could not put anything in it that
> wasn't an integer, and I'm not sure it would even be safe to
> put a bigint.  So most of the cases you might actually want
> (timestamp, bigserial, etc) would be ruled out.  Hardly worth
> inventing such a feature.

OK, I didn't realise it was the command tag that was the issue here. I took
a look at the libpq source to see how the INSERT tag works and it looks like
it currently assumes a string of numbers. So as a minimum it would need some
form of protocol extension to get this work (which I see from the archives
that you were not keen to pursue).

> How is what you're suggesting more portable?

I was hoping that it would only require minimal change (but obviously that
is not the case). I think, out of the remaining options, that keeping with
currval() is going to be the best approach - I can't really see the benefit
of using a non-SQL standard command just for SQL insertion, mainly as you
and others have suggested for portability reasons :(


Kind regards,

Mark.

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