pg_connect

pg_connect — Open a connection to the server

Synopsis

pg_connect -conninfo connectOptions
pg_connect dbName ?-host hostName? ?-port portNumber? ?-tty tty? ?-options serverOptions?

Description

pg_connect opens a connection to the PostgreSQL server.

Two syntax styles are available. In the older one, each possible option has a separate option switch in the pg_connect command. This syntax is deprecated and should not be used. In the newer style, a single option string is supplied that can contain multiple option values. pg_conndefaults can be used to retrieve information about the available options in the newer syntax style.

Connections opened with pg_connect should be closed with pg_disconnect once they are no longer needed.

Arguments

New style

-conninfo connectOptions

A string of connection options, each written in the form keyword = value. A list of valid options can be found in the description of the libpq function PQconnectdb. Some of the more common keywords are: host, port, dbname, user, and password. The keyword value must be placed in single quotes if it is empty or contains spaces. Within the single quotes, a single quote or backslash must be escaped by preceding it with a backslash.

Old style

dbName

The name of the database to connect to.

-host hostName

The host name of the database server to connect to.

-port portNumber

The TCP port number of the database server to connect to.

-tty tty

A file or TTY for optional debug output from the server.

-options serverOptions

Additional configuration options to pass to the server.

Return Value

If successful, a handle for a database connection is returned. Handles start with the prefix pgsql.

A Tcl error will be thrown if a connection could not be made. The Tcl error message indicates the reason.

Notes

This command uses or emulates the PostgreSQL libpq function PQconnectdb in the newer style, and the function PQsetdb for the older style.