clusterdb(1) - phpMan

CLUSTERDB(1) PostgreSQL 14.15 Documentation CLUSTERDB(1)

NAME
clusterdb - cluster a PostgreSQL database

SYNOPSIS
clusterdb [connection-option...] [--verbose | -v] [ --table | -t table ]... [dbname]

clusterdb [connection-option...] [--verbose | -v] --all | -a

DESCRIPTION
clusterdb is a utility for reclustering tables in a PostgreSQL database. It finds tables
that have previously been clustered, and clusters them again on the same index that was
last used. Tables that have never been clustered are not affected.

clusterdb is a wrapper around the SQL command CLUSTER(7). There is no effective difference
between clustering databases via this utility and via other methods for accessing the
server.

OPTIONS
clusterdb accepts the following command-line arguments:

-a
--all
Cluster all databases.

[-d] dbname
[--dbname=]dbname
Specifies the name of the database to be clustered, when -a/--all is not used. If this
is not specified, the database name is read from the environment variable PGDATABASE.
If that is not set, the user name specified for the connection is used. The dbname can
be a connection string. If so, connection string parameters will override any
conflicting command line options.

-e
--echo
Echo the commands that clusterdb generates and sends to the server.

-q
--quiet
Do not display progress messages.

-t table
--table=table
Cluster table only. Multiple tables can be clustered by writing multiple -t switches.

-v
--verbose
Print detailed information during processing.

-V
--version
Print the clusterdb version and exit.

-?
--help
Show help about clusterdb command line arguments, and exit.

clusterdb also accepts the following command-line arguments for connection parameters:

-h host
--host=host
Specifies the host name of the machine on which the server is running. If the value
begins with a slash, it is used as the directory for the Unix domain socket.

-p port
--port=port
Specifies the TCP port or local Unix domain socket file extension on which the server
is listening for connections.

-U username
--username=username
User name to connect as.

-w
--no-password
Never issue a password prompt. If the server requires password authentication and a
password is not available by other means such as a .pgpass file, the connection
attempt will fail. This option can be useful in batch jobs and scripts where no user
is present to enter a password.

-W
--password
Force clusterdb to prompt for a password before connecting to a database.

This option is never essential, since clusterdb will automatically prompt for a
password if the server demands password authentication. However, clusterdb will waste
a connection attempt finding out that the server wants a password. In some cases it is
worth typing -W to avoid the extra connection attempt.

--maintenance-db=dbname
Specifies the name of the database to connect to to discover which databases should be
clustered, when -a/--all is used. If not specified, the postgres database will be
used, or if that does not exist, template1 will be used. This can be a connection
string. If so, connection string parameters will override any conflicting command line
options. Also, connection string parameters other than the database name itself will
be re-used when connecting to other databases.

ENVIRONMENT
PGDATABASE
PGHOST
PGPORT
PGUSER
Default connection parameters

PG_COLOR
Specifies whether to use color in diagnostic messages. Possible values are always,
auto and never.

This utility, like most other PostgreSQL utilities, also uses the environment variables
supported by libpq (see Section 34.15).

DIAGNOSTICS
In case of difficulty, see CLUSTER(7) and psql(1) for discussions of potential problems
and error messages. The database server must be running at the targeted host. Also, any
default connection settings and environment variables used by the libpq front-end library
will apply.

EXAMPLES
To cluster the database test:

$ clusterdb test

To cluster a single table foo in a database named xyzzy:

$ clusterdb --table=foo xyzzy