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	Tue, 31 Aug 1999 10:07:08 -0400 (EDT)
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To: Thomas Lockhart <lockhart@alumni.caltech.edu>
cc: robertC@opmr.com, pgsql-interfaces@postgreSQL.org
Subject: Re: [INTERFACES] How do I drop a column from a table? 
From: Tatsuo Ishii <t-ishii@sra.co.jp>
Reply-To: t-ishii@sra.co.jp
In-reply-to: Your message of Tue, 31 Aug 1999 07:02:01 GMT.
	<37CB7DE9.D22E7E45@alumni.caltech.edu>
Date: Tue, 31 Aug 1999 22:59:38 +0900
Sender: t-ishii@ext04.sra.co.jp

> > I'm still quite new at this but it should be a simple operation:  How do I
> > drop a column form a Postgres table.  The next best thing would be knowing
> > how to change a column so that it can accept null values.
> 
> Adding columns is directly supported. Removing columns, or redefining
> them, is done with a CREATE TABLE AS/DROP TABLE/CREATE TABLE AS/DROP
> TABLE sequence, where you write the columns you want to retain into a
> temporary table, delete the original table, and then do the same back
> into a new table with the same name as the original.

But this method might lose some characteristics such as primary key,
unique constraints, no?
---
Tatsuo Ishii