vacuumdb — garbage-collect and analyze a PostgreSQL database
vacuumdb
[connection-option
...] [option
...] [ --table
| -t
table
[( column
[,...] )]
]
... [dbname
]
vacuumdb
[connection-option
...] [option
...] --all
| -a
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
--all
Vacuum all databases.
[-d] dbname
[--dbname=]dbname
Specifies the name of the database to be cleaned or analyzed.
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
used.
-e
--echo
Echo the commands that vacuumdb generates and sends to the server.
-f
--full
Perform “full” vacuuming.
-F
--freeze
Aggressively “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
--quiet
Do 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
--verbose
Print detailed information during processing.
-V
--version
Print the vacuumdb version and exit.
-z
--analyze
Also calculate statistics for use by the optimizer.
-Z
--analyze-only
Only 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.
-?
--help
Show help about vacuumdb command line arguments, and exit.
vacuumdb 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 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 discover what other
databases should be vacuumed. If not specified, the
postgres
database will be used,
and if that does not exist, template1
will be used.
PGDATABASE
PGHOST
PGPORT
PGUSER
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 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 33.15 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