pg_restore Man page

PG_RESTORE(1) PostgreSQL 9.5.5 Documentation PG_RESTORE(1)

NAME

pg_restore – restore a PostgreSQL database from an archive file created
by pg_dump

SYNOPSIS

pg_restore [connection-option…] [option…] [filename]

DESCRIPTION

pg_restore is a utility for restoring a PostgreSQL database from an
archive created by pg_dump in one of the non-plain-text formats. It
will issue the commands necessary to reconstruct the database to the
state it was in at the time it was saved. The archive files also allow
pg_restore to be selective about what is restored, or even to reorder
the items prior to being restored. The archive files are designed to be
portable across architectures.

pg_restore can operate in two modes. If a database name is specified,
pg_restore connects to that database and restores archive contents
directly into the database. Otherwise, a script containing the SQL
commands necessary to rebuild the database is created and written to a
file or standard output. This script output is equivalent to the plain
text output format of pg_dump. Some of the options controlling the
output are therefore analogous to pg_dump options.

Obviously, pg_restore cannot restore information that is not present in
the archive file. For instance, if the archive was made using the “dump
data as INSERT commands” option, pg_restore will not be able to load
the data using COPY statements.

OPTIONS

pg_restore accepts the following command line arguments.

filename
Specifies the location of the archive file (or directory, for a
directory-format archive) to be restored. If not specified, the
standard input is used.

-a
–data-only
Restore only the data, not the schema (data definitions). Table
data, large objects, and sequence values are restored, if present
in the archive.

This option is similar to, but for historical reasons not identical
to, specifying –section=data.

-c
–clean
Clean (drop) database objects before recreating them. (Unless
–if-exists is used, this might generate some harmless error
messages, if any objects were not present in the destination
database.)

-C
–create
Create the database before restoring into it. If –clean is also
specified, drop and recreate the target database before connecting
to it.

When this option is used, the database named with -d is used only
to issue the initial DROP DATABASE and CREATE DATABASE commands.
All data is restored into the database name that appears in the
archive.

-d dbname
–dbname=dbname
Connect to database dbname and restore directly into the database.

-e
–exit-on-error
Exit if an error is encountered while sending SQL commands to the
database. The default is to continue and to display a count of
errors at the end of the restoration.

-f filename
–file=filename
Specify output file for generated script, or for the listing when
used with -l. Default is the standard output.

-F format
–format=format
Specify format of the archive. It is not necessary to specify the
format, since pg_restore will determine the format automatically.
If specified, it can be one of the following:

c
custom
The archive is in the custom format of pg_dump.

d
directory
The archive is a directory archive.

t
tar
The archive is a tar archive.

-I index
–index=index
Restore definition of named index only. Multiple indexes may be
specified with multiple -I switches.

-j number-of-jobs
–jobs=number-of-jobs
Run the most time-consuming parts of pg_restore — those which load
data, create indexes, or create constraints — using multiple
concurrent jobs. This option can dramatically reduce the time to
restore a large database to a server running on a multiprocessor
machine.

Each job is one process or one thread, depending on the operating
system, and uses a separate connection to the server.

The optimal value for this option depends on the hardware setup of
the server, of the client, and of the network. Factors include the
number of CPU cores and the disk setup. A good place to start is
the number of CPU cores on the server, but values larger than that
can also lead to faster restore times in many cases. Of course,
values that are too high will lead to decreased performance because
of thrashing.

Only the custom and directory archive formats are supported with
this option. The input must be a regular file or directory (not,
for example, a pipe). This option is ignored when emitting a script
rather than connecting directly to a database server. Also,
multiple jobs cannot be used together with the option
–single-transaction.

-l
–list
List the contents of the archive. The output of this operation can
be used as input to the -L option. Note that if filtering switches
such as -n or -t are used with -l, they will restrict the items
listed.

-L list-file
–use-list=list-file
Restore only those archive elements that are listed in list-file,
and restore them in the order they appear in the file. Note that if
filtering switches such as -n or -t are used with -L, they will
further restrict the items restored.

list-file is normally created by editing the output of a previous
-l operation. Lines can be moved or removed, and can also be
commented out by placing a semicolon (;) at the start of the line.
See below for examples.

-n namespace
–schema=schema
Restore only objects that are in the named schema. Multiple schemas
may be specified with multiple -n switches. This can be combined
with the -t option to restore just a specific table.

-O
–no-owner
Do not output commands to set ownership of objects to match the
original database. By default, pg_restore issues ALTER OWNER or SET
SESSION AUTHORIZATION statements to set ownership of created schema
elements. These statements will fail unless the initial connection
to the database is made by a superuser (or the same user that owns
all of the objects in the script). With -O, any user name can be
used for the initial connection, and this user will own all the
created objects.

-P function-name(argtype [, …])
–function=function-name(argtype [, …])
Restore the named function only. Be careful to spell the function
name and arguments exactly as they appear in the dump file’s table
of contents. Multiple functions may be specified with multiple -P
switches.

-R
–no-reconnect
This option is obsolete but still accepted for backwards
compatibility.

-s
–schema-only
Restore only the schema (data definitions), not data, to the extent
that schema entries are present in the archive.

This option is the inverse of –data-only. It is similar to, but
for historical reasons not identical to, specifying
–section=pre-data –section=post-data.

(Do not confuse this with the –schema option, which uses the word
“schema” in a different meaning.)

-S username
–superuser=username
Specify the superuser user name to use when disabling triggers.
This is relevant only if –disable-triggers is used.

-t table
–table=table
Restore definition and/or data of named table only. Multiple tables
may be specified with multiple -t switches. This can be combined
with the -n option to specify a schema.

-T trigger
–trigger=trigger
Restore named trigger only. Multiple triggers may be specified with
multiple -T switches.

-v
–verbose
Specifies verbose mode.

-V
–version
Print the pg_restore version and exit.

-x
–no-privileges
–no-acl
Prevent restoration of access privileges (grant/revoke commands).

-1
–single-transaction
Execute the restore as a single transaction (that is, wrap the
emitted commands in BEGIN/COMMIT). This ensures that either all the
commands complete successfully, or no changes are applied. This
option implies –exit-on-error.

–disable-triggers
This option is relevant only when performing a data-only restore.
It instructs pg_restore to execute 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 –disable-triggers must be done
as superuser. So you should also specify a superuser name with -S
or, preferably, run pg_restore as a PostgreSQL superuser.

–enable-row-security
This option is relevant only when restoring the contents of a table
which has row security. By default, pg_restore will set
row_security to off, to ensure that all data is restored in to the
table. If the user does not have sufficient privileges to bypass
row security, then an error is thrown. This parameter instructs
pg_restore to set row_security to on instead, allowing the user to
attempt to restore the contents of the table with row security
enabled. This might still fail if the user does not have the right
to insert the rows from the dump into the table.

Note that this option currently also requires the dump be in INSERT
format, as COPY TO does not support row security.

–if-exists
Use conditional commands (i.e. add an IF EXISTS clause) when
cleaning database objects. This option is not valid unless –clean
is also specified.

–no-data-for-failed-tables
By default, table data is restored even if the creation command for
the table failed (e.g., because it already exists). With this
option, data for such a table is skipped. This behavior is useful
if the target database already contains the desired table contents.
For example, auxiliary tables for PostgreSQL extensions such as
PostGIS might already be loaded in the target database; specifying
this option prevents duplicate or obsolete data from being loaded
into them.

This option is effective only when restoring directly into a
database, not when producing SQL script output.

–no-security-labels
Do not output commands to restore security labels, even if the
archive contains them.

–no-tablespaces
Do not output commands to select tablespaces. With this option, all
objects will be created in whichever tablespace is the default
during restore.

–section=sectionname
Only restore the named section. The section name can be pre-data,
data, or post-data. This option can be specified more than once to
select multiple sections. The default is to restore all sections.

The data section contains actual table data as well as large-object
definitions. Post-data items consist of definitions of indexes,
triggers, rules and constraints other than validated check
constraints. Pre-data items consist of all other data definition
items.

–use-set-session-authorization
Output SQL-standard SET SESSION AUTHORIZATION commands instead of
ALTER OWNER commands to determine object ownership. This makes the
dump more standards-compatible, but depending on the history of the
objects in the dump, might not restore properly.

-?
–help
Show help about pg_restore command line arguments, and exit.

pg_restore 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. The default is taken from the
PGHOST environment variable, if set, else a Unix domain socket
connection is attempted.

-p port
–port=port
Specifies the TCP port or local Unix domain socket file extension
on which the server is listening for connections. Defaults to the
PGPORT environment variable, if set, or a compiled-in default.

-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 pg_restore to prompt for a password before connecting to a
database.

This option is never essential, since pg_restore will automatically
prompt for a password if the server demands password
authentication. However, pg_restore 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.

–role=rolename
Specifies a role name to be used to perform the restore. This
option causes pg_restore to issue a SET ROLE rolename command after
connecting to the database. It is useful when the authenticated
user (specified by -U) lacks privileges needed by pg_restore, but
can switch to a role with the required rights. Some installations
have a policy against logging in directly as a superuser, and use
of this option allows restores to be performed without violating
the policy.

ENVIRONMENT
PGHOST
PG

OPTIONS

PGPORT
PGUSER
Default connection parameters

This utility, like most other PostgreSQL utilities, also uses the
environment variables supported by libpq (see Section 31.14,
“Environment Variables”, in the documentation). However, it does not
read PGDATABASE when a database name is not supplied.

DIAGNOSTICS
When a direct database connection is specified using the -d option,
pg_restore internally executes SQL statements. If you have problems
running pg_restore, make sure you are able to select information from
the database using, for example, psql. Also, any default connection
settings and environment variables used by the libpq front-end library
will apply.

NOTES
If your installation has any local additions to the template1 database,
be careful to load the output of pg_restore 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:

CREATE DATABASE foo WITH TEMPLATE template0;

The limitations of pg_restore are detailed below.

· When restoring data to a pre-existing table and the option
–disable-triggers is used, pg_restore emits commands to disable
triggers on user tables before inserting the data, then emits
commands to re-enable them after the data has been inserted. If the
restore is stopped in the middle, the system catalogs might be left
in the wrong state.

· pg_restore cannot restore large objects selectively; for instance,
only those for a specific table. If an archive contains large
objects, then all large objects will be restored, or none of them
if they are excluded via -L, -t, or other options.

See also the pg_dump documentation for details on limitations of
pg_dump.

Once restored, it is wise to run ANALYZE on each restored table so the
optimizer has useful statistics; see Section 23.1.3, “Updating Planner
Statistics”, in the documentation and Section 23.1.6, “The Autovacuum
Daemon”, in the documentation for more information.

EXAMPLES
Assume we have dumped a database called mydb into a custom-format dump
file:

$ pg_dump -Fc mydb > db.dump

To drop the database and recreate it from the dump:

$ dropdb mydb
$ pg_restore -C -d postgres db.dump

The database named in the -d switch can be any database existing in the
cluster; pg_restore only uses it to issue the CREATE DATABASE command
for mydb. With -C, data is always restored into the database name that
appears in the dump file.

To reload the dump into a new database called newdb:

$ createdb -T template0 newdb
$ pg_restore -d newdb db.dump

Notice we don’t use -C, and instead connect directly to the database to
be restored into. Also note that we clone the new database from
template0 not template1, to ensure it is initially empty.

To reorder database items, it is first necessary to dump the table of
contents of the archive:

$ pg_restore -l db.dump > db.list

The listing file consists of a header and one line for each item, e.g.:

;
; Archive created at Mon Sep 14 13:55:39 2009
; dbname: DBDEMOS
; TOC Entries: 81
; Compression: 9
; Dump Version: 1.10-0
; Format: CUSTOM
; Integer: 4 bytes
; Offset: 8 bytes
; Dumped from database version: 8.3.5
; Dumped by pg_dump version: 8.3.8
;
;
; Selected TOC Entries:
;
3; 2615 2200 SCHEMA – public pasha
1861; 0 0 COMMENT – SCHEMA public pasha
1862; 0 0 ACL – public pasha
317; 1247 17715 TYPE public composite pasha
319; 1247 25899 DOMAIN public domain0 pasha

Semicolons start a comment, and the numbers at the start of lines refer
to the internal archive ID assigned to each item.

Lines in the file can be commented out, deleted, and reordered. For
example:

10; 145433 TABLE map_resolutions postgres
;2; 145344 TABLE species postgres
;4; 145359 TABLE nt_header postgres
6; 145402 TABLE species_records postgres
;8; 145416 TABLE ss_old postgres

could be used as input to pg_restore and would only restore items 10
and 6, in that order:

$ pg_restore -L db.list db.dump

SEE ALSO

pg_dump, pg_dumpall, psql

PostgreSQL 9.5.5 2016 PG_RESTORE(1)