Message-ID: <000d01c18b1e$9ba84320$8455e5ce@edison>
From: "Frank Morton" <fmorton@base2inc.com>
To: <pgsql-sql@postgresql.org>
References: <web-533913@davinci.ethosmedia.com>
Subject: JOIN question
Date: Sat, 22 Dec 2001 14:26:50 -0500
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I'm looking for the most portable way to do the following,
given these two tables:

Table 1 is called "content" which contains an integer "id" column.
The value of this id is "1" for this example.

Table 2 is called "protection" and keeps track of who can read
and write the content object, so this table may contain multiple
protection settings for a single content object.

Simplifying, to consider my problem, the protection table contains
a column called "contentId", connecting it to the content table id.
This table has three rows in it for three groups that can read it
with contentId set to "1".

If I do the query:

select Content.* from Content,Protection
where (Content.id = Protection.contentId);

I get three rows back, corresponding to each group that has
access to the content. However, I would like to get back
just one row, corresponding to the content that fits the desired
protections.

How do I do this?

Thanks for answering this question for the relative sql newbie.