Re: Function to Pivot data - Mailing list pgsql-general

From Andrew Sullivan
Subject Re: Function to Pivot data
Date
Msg-id 20020212114926.E30421@mail.libertyrms.com
Whole thread Raw
In response to Re: Function to Pivot data  (Bruno Wolff III <bruno@wolff.to>)
Responses Re: Function to Pivot data  (Bruno Wolff III <bruno@wolff.to>)
List pgsql-general
On Mon, Feb 11, 2002 at 07:39:38AM -0600, Bruno Wolff III wrote:

> The way I did this for a tiny book database I have set up for my wife
> to keep track of books is to have an edition table, an author table and
> a table of edition author pairs. It isn't ordered, but it could be
> by adding another field to the edition, author pairs.

That was my original suggestion.  But then, how do you make sure that
every edition has only one first author, only one second, &c.?  Also,
you can't have a generic query which gets the authors for every book,
and shows them in the tabular output that was originally desired
(hence the pivot table).  You could, however, write some code outside
the database which would first query the book_author table, figure
out how many authors were necessary, and then build the real query
that way.

A
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Andrew Sullivan                               87 Mowat Avenue
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