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NAMEvacuumdb - garbage-collect and analyze a PostgreSQL database SYNOPSISvacuumdb [connection-option...] [option...] [ -t | --table table [( column [,...] )] ]... [dbname | -a | --all] vacuumdb [connection-option...] [option...] [ -n | --schema schema ]... [dbname | -a | --all] vacuumdb [connection-option...] [option...] [ -N | --exclude-schema schema ]... [dbname | -a | --all] DESCRIPTIONvacuumdb 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. OPTIONSvacuumdb accepts the following command-line arguments: -a
Vacuum all databases.
--buffer-usage-limit size Specifies the Buffer Access Strategy ring buffer size for
a given invocation of vacuumdb. This size is used to calculate the number of
shared buffers which will be reused as part of this strategy. See
VACUUM(7).
[-d] 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.
--disable-page-skipping Disable skipping pages based on the contents of the
visibility map.
-e
Echo the commands that vacuumdb generates and sends to
the server.
-f
Perform “full” vacuuming.
-F
Aggressively “freeze” tuples.
--force-index-cleanup Always remove index entries pointing to dead
tuples.
-j njobs
Execute the vacuum or analyze commands in parallel by
running njobs commands simultaneously. This option may reduce the
processing time 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. --min-mxid-age mxid_age Only execute the vacuum or analyze commands on tables
with a multixact ID age of at least mxid_age. This setting is useful
for prioritizing tables to process to prevent multixact ID wraparound (see
Section 24.1.5.1).
For the purposes of this option, the multixact ID age of a relation is the greatest of the ages of the main relation and its associated TOAST table, if one exists. Since the commands issued by vacuumdb will also process the TOAST table for the relation if necessary, it does not need to be considered separately. --min-xid-age xid_age Only execute the vacuum or analyze commands on tables
with a transaction ID age of at least xid_age. This setting is useful
for prioritizing tables to process to prevent transaction ID wraparound (see
Section 24.1.5).
For the purposes of this option, the transaction ID age of a relation is the greatest of the ages of the main relation and its associated TOAST table, if one exists. Since the commands issued by vacuumdb will also process the TOAST table for the relation if necessary, it does not need to be considered separately. --missing-stats-only Only analyze relations that are missing statistics for a
column, index expression, or extended statistics object. This option prevents
vacuumdb from deleting existing statistics so that the query optimizer's
choices do not become transiently worse.
This option can only be used in conjunction with --analyze-only or --analyze-in-stages. -n schema
Clean or analyze all tables in schema only.
Multiple schemas can be vacuumed by writing multiple -n switches.
-N schema
Do not clean or analyze any tables in schema.
Multiple schemas can be excluded by writing multiple -N switches.
--no-index-cleanup Do not remove index entries pointing to dead
tuples.
--no-process-main Skip the main relation.
--no-process-toast Skip the TOAST table associated with the table to vacuum,
if any.
--no-truncate Do not truncate empty pages at the end of the
table.
-P parallel_workers
Specify the number of parallel workers for parallel
vacuum. This allows the vacuum to leverage multiple CPUs to process indexes.
See VACUUM(7).
-q
Do not display progress messages.
--skip-locked Skip relations that cannot be immediately locked for
processing.
-t 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.
Tip If you specify columns, you probably have to escape the parentheses from the shell. (See examples below.) -v
Print detailed information during processing.
-V
Print the vacuumdb version and exit.
-z
Also calculate statistics for use by the optimizer.
-Z
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 three stages of analyze; the first
stage uses the lowest possible statistics target (see
default_statistics_target) to produce usable statistics faster, and subsequent
stages build the full statistics.
This option is only useful to analyze a database that currently has no statistics or has wholly incorrect ones, such as if it is newly populated from a restored dump or by pg_upgrade. Be aware that running with this option in a database with existing statistics may cause the query optimizer choices to become transiently worse due to the low statistics targets of the early stages. -?
Show help about vacuumdb command line arguments, and
exit.
vacuumdb also accepts the following command-line arguments for connection parameters: -h 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
Specifies the TCP port or local Unix domain socket file
extension on which the server is listening for connections.
-U username
User name to connect as.
-w
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
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 When the -a/--all is used, connect to this
database to gather the list of databases to vacuum. 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.
ENVIRONMENTPGDATABASE
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 32.15). DIAGNOSTICSIn case of difficulty, see VACUUM(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. EXAMPLESTo 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 To clean all tables in the foo and bar schemas in a database named xyzzy: $ vacuumdb --schema='foo' --schema='bar' xyzzy SEE ALSOVACUUM(7)
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