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
clusterdb is a shell script wrapper around the
the PostgreSQL interactive terminal
psql. There is no effective
difference between clustering databases via this or other methods.
psql must be found by the script and
a database server must be running at the targeted host. Also, any default
settings and environment variables available to psql
and the libpq front-end library do apply.
clusterdb might need to connect several
times to the PostgreSQL server, asking for
a password each time. It is convenient to have a
$HOME/.pgpass file in such cases.
clusterdb accepts the following command-line arguments:
Cluster all databases.
- [-d] dbname
Specifies the name of the database to be clustered.
If this is not specified and -a (or
--all) is not used, the database name is read
from the environment variable PGDATABASE. If
that is not set, the user name specified for the connection is
Echo the commands that clusterdb generates
and sends to the server.
Do not display a response.
- -t table
Clusters table only.
clusterdb also accepts
the following command-line arguments for connection parameters:
- -h host
Specifies the host name of the machine on which the
is running. If host begins with a slash, it is used
as the directory for the Unix domain socket.
- -p port
Specifies the Internet TCP/IP port or local Unix domain socket file
extension on which the server
is listening for connections.
- -U username
User name to connect as
Force password prompt.
To cluster the database test:
$ clusterdb test
To cluster a single table
foo in a database named
$ clusterdb --table foo xyzzy