Hello,
How can one differential between apparently duplicated usernames?
For example I have a postgres id 'www' present within my pg_shadow/pg_user.
I recently installed a package and inadvertantly created another 'www' user.
I have managed to remove the duplicate user by deleting it from pg_shadow by
identifying it via its usesysid field.

How can I

1) Ensure I canot in future create duplicate names?
2) If duplicate users are possible by what other means can the
   various instances of them be referenced?

Stephen

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Sat, 26 Feb 2000 17:01:55 -0800
"Stephen Martin" <stephen@sealteam.demon.co.uk>
Hello,
as a post script to this..
Under normal circumstances one cannot add
another user of the same name (phew!:) )
I think this was the result of a setup
script
writing directly into pg_shadow and pg_user;

Stephen

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010000C9

-----Original Message-----
From: owner-pgsql-interfaces@postgreSQL.org
[mailto:owner-pgsql-interfaces@postgreSQL.org]On Behalf Of Stephen
Martin
Sent: Saturday, February 26, 2000 5:00 PM
To: pgsql-interfaces@postgreSQL.org
Subject: [INTERFACES] Date: Sat, 26 Feb 2000 17:01:55 -0800


Hello,
How can one differential between apparently duplicated usernames?
For example I have a postgres id 'www' present within my pg_shadow/pg_user.
I recently installed a package and inadvertantly created another 'www' user.
I have managed to remove the duplicate user by deleting it from pg_shadow by
identifying it via its usesysid field.

How can I

1) Ensure I canot in future create duplicate names?
2) If duplicate users are possible by what other means can the
   various instances of them be referenced?

Stephen

----------------------------------------------
010000C9


************


Sat, 26 Feb 2000 17:15:34 -0800
"Stephen Martin" <stephen@sealteam.demon.co.uk>
RE: [INTERFACES] Date: Sat, 26 Feb 2000 17:01:55 -0800
"Stephen Martin" <stephen@sealteam.demon.co.uk> writes:
> For example I have a postgres id 'www' present within my pg_shadow/pg_user.
> I recently installed a package and inadvertantly created another 'www' user.

> How can I
> 1) Ensure I canot in future create duplicate names?

There should probably be a unique index on pg_shadow's usename field,
and another one on the usesysid field (otherwise there's not a unique
map from sysids to users, which is bad since we use sysids as
referential keys in other tables).

I'm surprised this hasn't been pointed out before :-(

I'm not sure how difficult it would be to do it.  Just creating
an index with CREATE INDEX will not work, because pg_shadow is
an installation-wide table and its index must be as well.  There's
some routine somewhere in the backend that would have to be taught
about the index.

			regards, tom lane

Sat, 26 Feb 2000 20:47:08 -0500
Tom Lane <tgl@sss.pgh.pa.us>
Re: [INTERFACES] Date: Sat, 26 Feb 2000 17:01:55 -0800 