How to get the name of the current database from within PostgreSQL?

The function current_database() returns the name of the current database:

 SELECT current_database();

It's an SQL function, so you must call it as part of an SQL statement. PostgreSQL doesn't support running functions as standalone queries, and has no CALL statement like some other SQL engines, so you just use SELECT to call a function.

you can use "\conninfo" in psql

\c

prints something like

You are now connected to database "foobar" as user "squanderer".

Use this if you don't mind creating a new connection, because this is what happens. The \connect (shortened as \c) without all parameters will create a new connection identical to your current one. The current connection is closed.

See the \connect command spec on http://www.postgresql.org/docs/9.3/static/app-psql.html :

If any of dbname, username, host or port are omitted (...) , the value of that parameter from the previous connection is used.