If you are already connected to a database server with psql and you want to confirm that you've connected to the right place and in the right way, you can execute some, or all, of the following commands. Here is the command that shows the current_database:
SELECT current_database();
The following command shows the current_user ID:
SELECT current_user;
The next command shows the IP address and port of the current connection, unless you are using Unix sockets, in which case both values are NULL:
SELECT inet_server_addr(), inet_server_port();
A user's password is not accessible using general SQL for obvious reasons.
You may also need the following:
SELECT version();
From PostgreSQL version 9.1 onwards, you can also use ...
