From: Dean Gibson (DB Administrator) <postgresql@ultimeth.com>
To: pgsql-performance@postgresql.org
Subject: Re: Bypassing useless ORDER BY in a VIEW
Date: Thu, 28 Feb 2008 10:09:50 -0800
Message-ID: <47C6F8EE.1080409@ultimeth.com> (raw)
In-Reply-To: <8366.1204218820@sss.pgh.pa.us>
References: <36af4bed0802280631ja29c636w2256fb329e14b95e@mail.gmail.com>
<8366.1204218820@sss.pgh.pa.us>
On 2008-02-28 09:13, Tom Lane wrote:
> A rule of thumb is that ORDER BY in a view is bad design, IMHO.
>
> regards, tom lane
>
I was surprised to find out that apparently it's also a PostgreSQL
extension; standard SQL apparently disallows ORDER BY in VIEWs:
http://en.wikipedia.org/wiki/Order_by_(SQL)
When I found this out, I removed all the ORDER BYs from my VIEWs (which
had been there for the convenience of subsequent SELECTs).
Of course, where ORDER BY in a VIEW is really helpful, is with OFFSET
and/or LIMIT clauses (which are also PostgreSQL extensions), which is
equivalent to what you point out.
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To: pgsql-performance@postgresql.org
Cc: postgresql@ultimeth.com
Subject: Re: Bypassing useless ORDER BY in a VIEW
In-Reply-To: <47C6F8EE.1080409@ultimeth.com>
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