From: Andrew Sullivan <ajs@crankycanuck.ca>
To: 'pgsql-sql@postgresql.org' <pgsql-sql@postgresql.org>
Subject: Re: Column with recycled sequence value
Date: Thu, 13 Jan 2005 17:14:40 -0500
Message-ID: <20050113221440.GD31858@phlogiston.dyndns.org> (raw)
In-Reply-To: <1105653424.24795.111.camel@state.g2switchworks.com>
References: <ED4E30DD9C43D5118DFB00508BBBA76EB1654B@neptun.sonorys.at>
<1105649326.24795.99.camel@state.g2switchworks.com>
<20050113211903.GA41687@winnie.fuhr.org>
<1105651913.24795.102.camel@state.g2switchworks.com>
<20050113214349.GC31858@phlogiston.dyndns.org>
<1105653424.24795.111.camel@state.g2switchworks.com>
On Thu, Jan 13, 2005 at 03:57:04PM -0600, Scott Marlowe wrote:
> What cases are you thinking of? I've seen some very limited ones, like
Off the top of my head
- legacy application, closed, where you can't fix the source and can't
have larger than 32bit datatype, but you have another way to ensure
no dups.
- the queue-management item you mentioned.
- optimistic cases where a short search range is more important than
that a transaction doesn't fail on insert
- circular number spaces (xid uses this, after all)
> the time someone is thinking of doing so it's because a boss who doesn't
> get it wants a pretty list with no holes in the sequence or something
> equally silly.
Like they have some business problem they need solved, and doing it
this way is ugly but relatively cheap, and doing it the other way
means replacing 4 software systems and retraining 100 people. Is it
a pretty design? Probably not. Is it something that is, of all the
compromises available, the best one under the circumstances? I
dunno; I'd have to look at the circumstances. I think it's probably
usually a good idea to avoid this, sure, but I'm not willing to make
it a blanket statement.
A
--
Andrew Sullivan | ajs@crankycanuck.ca
The fact that technology doesn't work is no bar to success in the marketplace.
--Philip Greenspun
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-sql@postgresql.org
Cc: ajs@crankycanuck.ca
Subject: Re: Column with recycled sequence value
In-Reply-To: <20050113221440.GD31858@phlogiston.dyndns.org>
* 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