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Date: Fri, 08 Nov 2002 09:22:10 +0100
From: Christoph Haller <ch@rodos.fzk.de>
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To: ho@optimasoft.com.tw
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Subject: Re: how to get the source table & field name of a view field
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>
> if I want to write a function for getting the view.field's source
> table.field
> how could I achieve it?
>
This sounds like a real challange.
Throughout the years I've had to learn it's always a pain to
retrieve system catalog information - no matter which
DBMS is in use.
On the other hand, you have to face the fact that
view.field's sources are not necessarily directly derived
from a table.field.
A view.field's source may be any expression including aggregates.

So, the only way I can think of achieving that is

SELECT definition from pg_views where viewname='<your view name>';

and then your function has to parse the result. Good luck.

Regards, Christoph