Message-ID: <43D8FA03.304@commandprompt.com>
Date: Thu, 26 Jan 2006 08:34:11 -0800
From: "Joshua D. Drake" <jd@commandprompt.com>
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To: J@Planeti.Biz
CC: pgsql-performance@postgresql.org
Subject: Re: Query optimization with X Y JOIN
References: <786c2f6d0601260206k2201a548p48af7c7fc085d3b2@mail.gmail.com>
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J@Planeti.Biz wrote:
> If I want my database to go faster, due to X then I would think that 
> the issue is about performance. I wasn't aware of a paticular 
> constraint on X.
>
> I have more that a rudementary understanding of what's going on here, 
> I was just hoping that someone could shed some light on the basic 
> principal of this JOIN command and its syntax. Most people I ask, 
> don't give me straight answers and what I have already read on the web 
> is not very helpful thus far.
What you are looking for is here:

http://sqlzoo.net/

It is an excellent website that discusses in depth but at a tutorial 
style level how and what SQL is and how to use it. Including JOINS.

FYI, a JOIN is basically a FROM with an integrated WHERE clause. That is 
a very simplified description and isn't 100% accurate
but it is close. I strongly suggest the website I mentioned above as it 
will resolve your question.

Joshua D. Drake

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