I have a user set up in a postgresql DB and am trying to delete the user and the db.
When I use dropdb, I get the message "failed to delete, there are 6 sessions still using this DB".

Does any one have any suggestions please?

Disconnect all sessions first.

Thank you

But how do I disconnect all of the sessions? please.

The clean way is to shut down those applications that are establishing those connections.
You can use the pg_stat_activity view (see http://www.postgresql.org/docs/curre...ing-stats.html) to find out what applications are connecting (and from where).

If you want to do it the hard way, you can use pg_terminate_backend() to kill those sessions.
For details see here: http://www.postgresql.org/docs/curre...N-SIGNAL-TABLE