Re: Bypassing useless ORDER BY in a VIEW

From: "Dean Gibson (DB Administrator)" <postgresql(at)ultimeth(dot)com>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: Bypassing useless ORDER BY in a VIEW
Date: 2008-02-28 18:09:50
Message-ID: 47C6F8EE.1080409@ultimeth.com
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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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