Message-ID: <4C4A0DEB.9060501@emolecules.com>
Date: Fri, 23 Jul 2010 14:47:23 -0700
From: Craig James <craig_james@emolecules.com>
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To: pgsql-performance@postgresql.org
Subject: Re: Using more tha one index per table
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On 7/23/10 2:22 AM, Torsten Zühlsdorff wrote:
> Craig James schrieb:
>
>>>> A useful trick to know is that if you replace the version number
>>>> with "current", you'll get to the latest version most of the time
>>>> (sometimes the name of the page is changed between versions, too, but
>>>> this isn't that frequent).
>>>
>>> The docs pages could perhaps benefit from an auto-generated note saying:
>>>
>>> "The current version of Pg is 8.4. This documentation is for version
>>> 8.2. Click [here] for documentation on the current version."
>>>
>>> ... or something to that effect. It'd be a nice (and more user-friendly)
>>> alternative to url twiddling when searches reveal docs for an old
>>> version, and might help push the /current/ pages up in search rank too.
>>
>> In addition, why not use symlinks so that the current version is
>> simply called "current", as in
>>
>> http://www.postgresql.org/docs/current/static/sql-insert.html
>>
>> If you google for "postgres insert", you get this:
>>
>> http://www.postgresql.org/docs/8.1/static/sql-insert.html
>>
>> The problem is that Google ranks pages based on inbound links, so
>> older versions of Postgres *always* come up before the latest version
>> in page ranking.
>
> Since 2009 you can deal with this by defining the canonical-version.
> (http://googlewebmastercentral.blogspot.com/2009/02/specify-your-canonical.html)

This is a really cool feature, but it's not what we need.  The "canonical" refers to the URL, not the web page.  It's only supposed to be used if you have multiple URLs that are actually the *same* page; the "canonical" URL tells Google "use only this URL for this page."

But in our case, the Postgres manuals for each release have different URLs *and* different content, so the "canonical URL" isn't the right solution.

Craig

> Greetings from Germany,
> Torsten
>