clusterdb — cluster a PostgreSQL database
-v ] [
table ] ... [
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. There is no effective difference between clustering databases via this utility and via other methods for accessing the server.
clusterdb accepts the following command-line arguments:
Cluster all databases.
Specifies the name of the database to be clustered. If this is
not specified and
--all) is not used, the database name is read from
the environment variable
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 progress messages.
Multiple tables can be clustered by writing multiple
Print detailed information during processing.
Print the clusterdb version and exit.
Show help about clusterdb command line arguments, and exit.
clusterdb also accepts the following command-line arguments for connection parameters:
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.
Specifies the TCP port or local Unix domain socket file extension on which the server is listening for connections.
User name to connect as.
Never issue a password prompt. If the server requires password
authentication and a password is not available by other means such
.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.
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.
Specifies the name of the database to connect to discover what
other databases should be clustered. If not specified, the
postgres database will be used, and if
that does not exist,
template1 will be
Default connection parameters
This utility, like most other PostgreSQL utilities, also uses the environment variables supported by libpq (see Section 33.14).
In case of difficulty, see CLUSTER and psql 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.
To cluster the database
To cluster a single table
foo in a
clusterdb --table=foo xyzzy
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