pg_dump.1

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\fItable\fR parameter is
interpreted as a pattern according to the same rules used by
\fBpsql\fR's \\d commands (see Patterns [\fBpsql\fR(1)]),
so multiple tables can also be selected by writing wildcard characters
in the pattern. When using wildcards, be careful to quote the pattern
if needed to prevent the shell from expanding the wildcards.

The \fB-n\fR and \fB-N\fR switches have no effect when
\fB-t\fR is used, because tables selected by \fB-t\fR will
be dumped regardless of those switches, and non-table objects will not
be dumped.
.sp
.RS
.B "Note:"
When \fB-t\fR is specified, \fBpg_dump\fR
makes no attempt to dump any other database objects that the selected
table(s) may depend upon. Therefore, there is no guarantee
that the results of a specific-table dump can be successfully
restored by themselves into a clean database.
.RE
.sp
.sp
.RS
.B "Note:"
The behavior of the \fB-t\fR switch is not entirely upward
compatible with pre-8.2 PostgreSQL
versions. Formerly, writing -t tab would dump all
tables named tab, but now it just dumps whichever one
is visible in your default search path. To get the old behavior
you can write -t '*.tab'. Also, you must write something
like -t sch.tab to select a table in a particular schema,
rather than the old locution of -n sch -t tab.
.RE
.sp
.TP
\fB-T \fItable\fB\fR
.TP
\fB--exclude-table=\fItable\fB\fR
Do not dump any tables matching the \fItable\fR pattern. The pattern is
interpreted according to the same rules as for \fB-t\fR.
\fB-T\fR can be given more than once to exclude tables
matching any of several patterns.

When both \fB-t\fR and \fB-T\fR are given, the behavior
is to dump just the tables that match at least one \fB-t\fR
switch but no \fB-T\fR switches. If \fB-T\fR appears
without \fB-t\fR, then tables matching \fB-T\fR are
excluded from what is otherwise a normal dump.
.TP
\fB-v\fR
.TP
\fB--verbose\fR
Specifies verbose mode. This will cause
\fBpg_dump\fR to output detailed object
comments and start/stop times to the dump file, and progress
messages to standard error.
.TP
\fB-x\fR
.TP
\fB--no-privileges\fR
.TP
\fB--no-acl\fR
Prevent dumping of access privileges (grant/revoke commands).
.TP
\fB--disable-dollar-quoting\fR
This option disables the use of dollar quoting for function bodies,
and forces them to be quoted using SQL standard string syntax.
.TP
\fB--disable-triggers\fR
This option is only relevant when creating a data-only dump.
It instructs \fBpg_dump\fR to include commands
to temporarily disable triggers on the target tables while
the data is reloaded. Use this if you have referential
integrity checks or other triggers on the tables that you
do not want to invoke during data reload.

Presently, the commands emitted for \fB--disable-triggers\fR
must be done as superuser. So, you should also specify
a superuser name with \fB-S\fR, or preferably be careful to
start the resulting script as a superuser.

This option is only meaningful for the plain-text format. For
the archive formats, you may specify the option when you
call \fBpg_restore\fR.
.TP
\fB--use-set-session-authorization\fR
Output SQL-standard \fBSET SESSION AUTHORIZATION\fR commands
instead of \fBALTER OWNER\fR commands to determine object
ownership. This makes the dump more standards compatible, but
depending on the history of the objects in the dump, may not restore
properly. Also, a dump using \fBSET SESSION AUTHORIZATION\fR
will certainly require superuser privileges to restore correctly,
whereas \fBALTER OWNER\fR requires lesser privileges.
.TP
\fB-Z \fI0..9\fB\fR
.TP
\fB--compress=\fI0..9\fB\fR
Specify the compression level to use in archive formats that
support compression. (Currently only the custom archive
format supports compression.)
.PP
.PP
The following command-line options control the database connection parameters.
.TP
\fB-h \fIhost\fB\fR
.TP
\fB--host=\fIhost\fB\fR
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. The default is taken
from the \fBPGHOST\fR environment variable, if set,
else a Unix domain socket connection is attempted.
.TP
\fB-p \fIport\fB\fR
.TP
\fB--port=\fIport\fB\fR
Specifies the TCP port or local Unix domain socket file
extension on which the server is listening for connections.
Defaults to the \fBPGPORT\fR environment variable, if
set, or a compiled-in default.
.TP
\fB-U \fIusername\fB\fR
Connect as the given user
.TP
\fB-W\fR
Force a password prompt. This should happen automatically if
the server requires password authentication.
.PP
.SH "ENVIRONMENT"
.TP
\fBPGDATABASE\fR
.TP
\fBPGHOST\fR
.TP
\fBPGPORT\fR
.TP
\fBPGUSER\fR
Default connection parameters.
.PP
This utility, like most other PostgreSQL utilities,
also uses the environment variables supported by \fBlibpq\fR
(see in the documentation).
.PP
.SH "DIAGNOSTICS"
.PP
\fBpg_dump\fR internally executes
\fBSELECT\fR statements. If you have problems running
\fBpg_dump\fR, make sure you are able to
select information from the database using, for example, \fBpsql\fR(1). Also, any default connection settings and environment
variables used by the \fBlibpq\fR front-end
library will apply.
.SH "NOTES"
.PP
If your database cluster has any local additions to the template1 database,
be careful to restore the output of \fBpg_dump\fR into a
truly empty database; otherwise you are likely to get errors due to
duplicate definitions of the added objects. To make an empty database
without any local additions, copy from template0 not template1,
for example:
.sp
.nf
CREATE DATABASE foo WITH TEMPLATE template0;
.sp
.fi
.PP
\fBpg_dump\fR has a few limitations:
.TP 0.2i
\(bu
When a data-only dump is chosen and the option
\fB--disable-triggers\fR is used,
\fBpg_dump\fR emits commands to disable
triggers on user tables before inserting the data and commands
to re-enable them after the data has been inserted. If the
restore is stopped in the middle, the system catalogs may be
left in the wrong state.
.PP
.PP
Members of tar archives are limited to a size less than 8 GB.
(This is an inherent limitation of the tar file format.) Therefore
this format cannot be used if the textual representation of any one table
exceeds that size. The total size of a tar archive and any of the
other output formats is not limited, except possibly by the
operating system.
.PP
The dump file produced by \fBpg_dump\fR does
not contain the statistics used by the optimizer to make query
planning decisions. Therefore, it is wise to run
\fBANALYZE\fR after restoring from a dump file to
ensure good performance.
.PP
Because \fBpg_dump\fR is used to transfer data
to newer versions of PostgreSQL, the output of
\fBpg_dump\fR can be loaded into
newer PostgreSQL databases. It also can read older
PostgreSQL databases. However, it usually cannot
read newer PostgreSQL databases or produce dump output
that can be loaded into older database versions. To do this, manual
editing of the dump file might be required.
.SH "EXAMPLES"
.PP
To dump a database called mydb into a SQL-script file:
.sp
.nf
$ \fBpg_dump mydb > db.sql\fR
.sp
.fi
.PP
To reload such a script into a (freshly created) database named
newdb:
.sp
.nf
$ \fBpsql -d newdb -f db.sql\fR
.sp
.fi
.PP
To dump a database into a custom-format archive file:
.sp
.nf
$ \fBpg_dump -Fc mydb > db.dump\fR
.sp
.fi
.PP
To reload an archive file into a (freshly created) database named
newdb:
.sp
.nf
$ \fBpg_restore -d newdb db.dump\fR
.sp
.fi
.PP
To dump a single table named mytab:
.sp
.nf
$ \fBpg_dump -t mytab mydb > db.sql\fR
.sp
.fi
.PP
To dump all tables whose names start with emp in the
detroit schema, except for the table named
employee_log:
.sp
.nf
$ \fBpg_dump -t 'detroit.emp*' -T detroit.employee_log mydb > db.sql\fR
.sp
.fi
.PP
To dump all schemas whose names start with east or
west and end in gsm, excluding any schemas whose
names contain the word test:
.sp
.nf
$ \fBpg_dump -n 'east*gsm' -n 'west*gsm' -N '*test*' mydb > db.sql\fR
.sp
.fi
.PP
The same, using regular expression notation to consolidate the switches:
.sp
.nf
$ \fBpg_dump -n '(east|west)*gsm' -N '*test*' mydb > db.sql\fR
.sp
.fi
.PP
To dump all database objects except for tables whose names begin with
ts_:
.sp
.nf
$ \fBpg_dump -T 'ts_*' mydb > db.sql\fR
.sp
.fi
.PP
To specify an upper-case or mixed-case name in \fB-t\fR and related
switches, you need to double-quote the name; else it will be folded to
lower case (see Patterns [\fBpsql\fR(1)]). But
double quotes are special to the shell, so in turn they must be quoted.
Thus, to dump a single table with a mixed-case name, you need something
like
.sp
.nf
$ \fBpg_dump -t '"MixedCaseName"' mydb > mytab.sql\fR
.sp
.fi
.SH "HISTORY"
.PP
The \fBpg_dump\fR utility first appeared in
\fBPostgres95\fR release 0.02. The
non-plain-text output formats were introduced in
PostgreSQL release 7.1.
.SH "SEE ALSO"
\fBpg_dumpall\fR(1), \fBpg_restore\fR(1), \fBpsql\fR(1)