Message-ID: <3D51950D.7090004@wildbrain.com>
Date: Wed, 07 Aug 2002 14:45:49 -0700
From: Gregory Brauer <greg@wildbrain.com>
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To: pgsql-sql@postgresql.org
Subject: Altering live databases
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I am starting to do a test run of maintaining a live database,
and I'm trying to figure out how to add a relation to an existing
table.  Lets say I do:

CREATE TABLE something
   (
     id           serial         ,
   );


And later I decide I *really* wish I had done:

CREATE TABLE something
   (
     id           serial         ,
     foo_id     int4            not null,

     foreign key(foo_id) references foo(id) on update CASCADE,
   );


How can I update a live database to add the missing relation?

So far I know that I need to:

ALTER TABLE issue_transaction ADD COLUMN foo_id int4 not null;


But how do I declare the foreign key and how do I declare the
ON UPDATE?  Is this something that is better done from a
backup?  I've noticed the trigger syntax in a backup isn't
exactly friendly, and the TOC Entry IDs are numbered, but I
woudn't know what number to use to create a new one.

Advice?

Greg