ERROR: Relation "pg_user" does not exist

Hi there!

I'm really new at this game, so please forgive me if my request is at
all irritating. I have installed PostgreSQL onto a Debian/Linux machine,
and I have just upgraded PostgreSQL via the apt-get update & upgrade
commands. However, whenever I get into the PostgreSQL interactive
terminal thus

sp(at)vanthoff:~$ psql -U postgres SHG

it returns this:

ERROR: Relation "pg_user" does not exist
Welcome to psql, the PostgreSQL interactive terminal.

Type: \copyright for distribution terms
\h for help with SQL commands
\? for help on internal slash commands
\g or terminate with semicolon to execute query
\q to quit

Now, if I try to connect to the database SHG:

SHG=> \c SHG

it returns this:

You are now connected to database SHG.
ERROR: Relation "pg_user" does not exist

These errors are encountered even when I'm logged on as root. I'm not
sure what other information you would require from me to answer this
question, so please do not hesitate to ask for it. Has anyone ever come
across this problem, and if so, how was it resolved? Many thanks in
advance.

Regards,

Sam.

--
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Sam Peppe Tel : +44 (0)23 8059 3587
Postdoctoral Research Fellow Fax : +44 (0)23 8059 3781
Department of Chemistry Email : samp(at)soton(dot)ac(dot)uk
University of Southampton
HANTS SO17 1BJ http://www.combechem.org/
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