NAME

       pg_wrapper - wrapper for PostgreSQL client commands

SYNOPSIS

       client-program [--cluster version/cluster] [...]

       (client-program: psql, createdb, dropuser, and all other client programs installed in
       /usr/lib/postgresql/version/bin).

DESCRIPTION

       This program is run only as a link to names which correspond to PostgreSQL programs in
       /usr/lib/postgresql/version/bin. It determines the configured cluster and database for the user and calls
       the appropriate version of the desired program to connect to that cluster and database, supplying any
       specified options to that command.

       The target cluster is selected by the following means, in descending order of precedence:

       1.  explicit specification with the --host option

       2.  explicit specification with the --cluster option

       3.  if  the  PGHOST  environment  variable is set, no further cluster selection is performed. The default
           PostgreSQL version and port number (from the  command  line,  the  environment  variable  PGPORT,  or
           default 5432) will be used.

       4.  explicit specification with the PGCLUSTER environment variable

       5.  matching entry in ~/.postgresqlrc (see postgresqlrc(5)), if that file exists

       6.  matching entry in /etc/postgresql-common/user_clusters (see user_clusters(5)), if that file exists

       7.  If only one cluster exists on the local system, that one will be selected.

       8.  If  several  clusters  exist  on the local system, the one listening on the default port 5432 will be
           selected.

       If none of these rules match, pg_wrapper does not set any environment variables and  the  program  called
       will likely error out with a message like "could not connect to server: Connection refused".

       For  psql,  pg_archivecleanup,  and  pg_isready,  pg_wrapper  will  always use the binary from the newest
       PostgreSQL version installed, as these are downwards compatible.

       Note that pg_wrapper needs to be able to read the server config to get the port number to connect to.  If
       a  non-standard  port  is  configured  in a place that pg_wrapper cannot read, connecting will fail. This
       particularly holds if the port was configured via ALTER SYSTEM in postgresql.auto.conf and pg_wrapper  is
       invoked as any user other than postgres and root.

OPTIONS

       --cluster version/cluster
       --cluster version/host:[port]
           cluster is either the name of a cluster on the local system, or takes the form host:port for a remote
           cluster. If port is left empty (i. e. you just specify host:), it defaults to 5432.

ENVIRONMENT

       PGCLUSTER
           If  $PGCLUSTER is set, its value (of the form version/cluster) specifies the desired cluster, similar
           to the --cluster option. However, if --cluster is specified, it overrides the value of $PGCLUSTER.

       PG_CLUSTER_CONF_ROOT
           This  specifies  an  alternative  base  directory  for  cluster  configurations.  This   is   usually
           /etc/postgresql/,  but  for  testing/development  purposes you can change this to point to e. g. your
           home directory, so that you can use the postgresql-common tools without root privileges.

       PGSYSCONFDIR
           This  is  the  location  of  PostgreSQL's  and  postgresql-common's  global  configuration   (e.   g.
           pg_service.conf, user_clusters(5)). The default is /etc/postgresql-common/.

FILES

       /etc/postgresql-common/user_clusters
           stores the default cluster and database for users and groups as set by the administrators.

       $HOME/.postgresqlrc
           stores defaults set by the user himself.

SEE ALSO

       user_clusters(5), postgresqlrc(5)

AUTHOR

       Martin Pitt <mpitt@debian.org>

Debian                                             2022-02-10                                      PG_WRAPPER(1)