The following environment variables can be used to select default
connection parameter values, which will be used by PQconnectdb or
PQsetdbLogin if no value is directly specified by the calling code.
These are useful to avoid hard-coding database names into simple
application programs.
PGHOST sets the default server name.
If this begins with a slash, it specifies Unix-domain communication
rather than TCP/IP communication; the value is the name of the
directory in which the socket file is stored (default /tmp).
PGPORT sets the default TCP port number or Unix-domain
socket file extension for communicating with the
PostgreSQL backend.
PGDATABASE sets the default
PostgreSQL database name.
PGUSER
sets the user name used to connect to the database and for authentication.
PGPASSWORD
sets the password used if the backend demands password
authentication. This functionality is deprecated for security
reasons; consider migrating to use the $HOME/.pgpass
file.
PGREALM sets the Kerberos realm to use with
PostgreSQL, if it is different from the local realm.
If PGREALM is set, PostgreSQL
applications will attempt authentication with servers for this realm and use
separate ticket files to avoid conflicts with local
ticket files. This environment variable is only
used if Kerberos authentication is selected by the backend.
PGOPTIONS sets additional run-time options for
the PostgreSQL backend.
PGTTY sets the file or tty on which debugging
messages from the backend server are displayed.
The following environment variables can be used to specify user-level default
behavior for every PostgreSQL session:
PGDATESTYLE
sets the default style of date/time representation.
PGTZ
sets the default time zone.
PGCLIENTENCODING
sets the default client encoding (if multibyte support was selected
when configuring PostgreSQL).
The following environment variables can be used to specify default internal
behavior for every PostgreSQL session:
Refer to the SET SQL command
for information on correct values for these environment variables.
