Using \c <database_name> in PostgreSQL will connect to the named database.
How can the name of the current database be determined?
Entering:
my_db> current_database();
produces:
ERROR: syntax error at or near "current_database"
LINE 1: current_database();
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.
CALL.
SELECT current_user, the fact that current_database is a function is surprising.
current_user as a magic keyword. Postgres does not want to expand the set of keywords, so anything not specified by the standard tends to be added as functions.
ALTER DATABASE .. query, I need dynamic sql or psql vars I reckon. @SteveChavez btw there is current_catalog, see this answer.
ALTER DATABASE cannot run in a function context. Maybe it can as a PROCEDURE. I haven't checked. Try a PL/PgSQL PROCEDURE with an EXECUTE block.
you can use "\conninfo" in psql
psql version 9.1. That should cover basically all the psql clients out there these days, though.
\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.
SELECT * FROM current_catalog;
-- and
SELECT current_catalog;
...both work as well (catalog is standard SQL for database)
PostgreSQL List Databases - To list all the databases created within PostgreSQL Server.
postgres=# \l
postgres=# \list
To Check Current database you are connected to.
SELECT current_database();
Using INFORMATION_SCHEMA views:
information_schema_catalog_name
information_schema_catalog_name is a table that always contains one row and one column containing the name of the current database (current catalog, in SQL terminology).
SELECT * FROM INFORMATION_SCHEMA.INFORMATION_SCHEMA_CATALOG_NAME;
-- catalog_name
-- <name>
