vacuumdb — garbage-collect and analyze a PostgreSQL database
vacuumdb [connection-option...] [option...]
[
-t | --table
table
[( column [,...] )]
]
... [dbname]
vacuumdb [connection-option...] [option...] -a | --all
vacuumdb is a utility for cleaning a PostgreSQL database. vacuumdb will also generate internal statistics used by the PostgreSQL query optimizer.
vacuumdb is a wrapper around the SQL command VACUUM. There is no effective difference between vacuuming and analyzing databases via this utility and via other methods for accessing the server.
vacuumdb accepts the following command-line arguments:
-a--allVacuum all databases.
[-d] dbname[--dbname=]dbname
Specifies the name of the database to be cleaned or analyzed,
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--echoEcho the commands that vacuumdb generates and sends to the server.
-f--fullPerform “full” vacuuming.
-F--freezeAggressively “freeze” tuples.
-j njobs--jobs=njobs
Execute the vacuum or analyze commands in parallel by running
njobs
commands simultaneously. This option reduces the time of the
processing but it also increases the load on the database server.
vacuumdb will open
njobs connections to the
database, so make sure your max_connections
setting is high enough to accommodate all connections.
Note that using this mode together with the -f
(FULL) option might cause deadlock failures if
certain system catalogs are processed in parallel.
-q--quietDo not display progress messages.
-t table [ (column [,...]) ]--table=table [ (column [,...]) ]
Clean or analyze table only.
Column names can be specified only in conjunction with
the --analyze or --analyze-only options.
Multiple tables can be vacuumed by writing multiple
-t switches.
If you specify columns, you probably have to escape the parentheses from the shell. (See examples below.)
-v--verbosePrint detailed information during processing.
-V--versionPrint the vacuumdb version and exit.
-z--analyzeAlso calculate statistics for use by the optimizer.
-Z--analyze-onlyOnly calculate statistics for use by the optimizer (no vacuum).
--analyze-in-stages
Only calculate statistics for use by the optimizer (no vacuum),
like --analyze-only. Run several (currently three)
stages of analyze with different configuration settings, to produce
usable statistics faster.
This option is useful to analyze a database that was newly populated
from a restored dump or by pg_upgrade. This option
will try to create some statistics as fast as possible, to make the
database usable, and then produce full statistics in the subsequent
stages.
-?--helpShow help about vacuumdb command line arguments, and exit.
vacuumdb also accepts the following command-line arguments for connection parameters:
-h host--host=hostSpecifies 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=portSpecifies the TCP port or local Unix domain socket file extension on which the server is listening for connections.
-U username--username=usernameUser 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--passwordForce vacuumdb to prompt for a password before connecting to a database.
This option is never essential, since
vacuumdb will automatically prompt
for a password if the server demands password authentication.
However, vacuumdb 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 vacuumed,
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.
PGDATABASEPGHOSTPGPORTPGUSERDefault connection parameters
This utility, like most other PostgreSQL utilities, also uses the environment variables supported by libpq (see Section 34.14).
In case of difficulty, see VACUUM 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.
vacuumdb might need to connect several
times to the PostgreSQL server, asking
for a password each time. It is convenient to have a
~/.pgpass file in such cases. See Section 34.15 for more information.
To clean the database test:
$vacuumdb test
To clean and analyze for the optimizer a database named
bigdb:
$vacuumdb --analyze bigdb
To clean a single table
foo in a database named
xyzzy, and analyze a single column
bar of the table for the optimizer:
$vacuumdb --analyze --verbose --table='foo(bar)' xyzzy