Message-ID: <42275B20.6030108@logix-tt.com>
Date: Thu, 03 Mar 2005 19:44:48 +0100
From: Markus Schaber <schabi@logix-tt.com>
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To: "Casey T. Deccio" <ctdecci@sandia.gov>
Cc: pgsql-sql@postgresql.org
Subject: Re: Building a database from a flat file
References: <1109808921.12430.75.camel@boomerang.ran.sandia.gov>
	<42272D27.4030900@logix-tt.com>
	<1109875028.12428.98.camel@boomerang.ran.sandia.gov>
In-Reply-To: <1109875028.12428.98.camel@boomerang.ran.sandia.gov>
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Hi, Casey,

Casey T. Deccio schrieb:

> Question: is there an "easy" way to duplicate an existing schema
> (tables, functions, sequences, etc.)--not the data; only the schema?
> This way, I would only need to modify one schema (public) to make
> changes, and the build schema could be created each time as a duplicate
> of the public schema.  Maintenance would be much simpler.

I do not know about schemas, but for tables you can "CREATE TABLE alpha
(LIKE beta)".

>>- Create the new data in differently named tables, and then simply
>>rename all the old and new tables for "switch over".
> This probably would work too, but there may be problems with foreign
> keys in renaming the tables one at a time (unless deferrable is used).
> To avoid any mess, the previous one works well.

AFAIK, the foreign key relations are adopted when a table is renamed,
they stick to the same table disregarding name changes.


Markus
-- 
Markus Schaber | Dipl. Informatiker | Software Development GIS

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