pg_restore

Name

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

Synopsis

pg_restore [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, the archive is restored directly into the database. (Large objects can only be restored by using such a direct database connection.) Otherwise, a script containing the SQL commands necessary to rebuild the database is created (and written to a file or standard output), similar to the ones created by the pg_dump plain text format. Some of the options controlling the script 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 to be restored. If not specified, the standard input is used.

-a
--data-only

Restore only the data, not the schema (data definitions).

-c
--clean

Clean (drop) database objects before recreating them.

-C
--create

Create the database before restoring into it. (When this option is used, the database named with -d is used only to issue the initial CREATE DATABASE command. 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.

-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:

t

The archive is a tar archive. Using this archive format allows reordering and/or exclusion of schema elements at the time the database is restored. It is also possible to limit which data is reloaded at restore time.

c

The archive is in the custom format of pg_dump. This is the most flexible format in that it allows reordering of data load as well as schema elements. This format is also compressed by default.

-i
--ignore-version

Ignore database version checks.

-I index
--index=index

Restore definition of named index only.

-l
--list

List the contents of the archive. The output of this operation can be used with the -L option to restrict and reorder the items that are restored.

-L list-file
--use-list=list-file

Restore elements in list-file only, and in the order they appear in the file. Lines can be moved and may also be commented out by placing a ; at the start of the line. (See below for examples.)

-N
--orig-order

Restore items in the order they were originally generated within pg_dump. This option has no known practical use, since pg_dump generates the items in an order convenient to it, which is unlikely to be a safe order for restoring them. (This is not the order in which the items are ultimately listed in the archive's table of contents.) See also -r.

-o
--oid-order

Restore items in order by OID. This option is of limited usefulness, since OID is only an approximate indication of original creation order. This option overrides -N if both are specified. See also -r.

-O
--no-owner

Prevent any attempt to restore original object ownership. Objects will be owned by the user name used to attach to the database. See also under -R and -X use-set-session-authorization.

-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.

-r
--rearrange

Rearrange items by object type (this occurs after the sorting specified by -N or -o, if given). The rearrangement is intended to give the best possible restore performance.

When none of -N, -o, and -r appear, pg_restore restores items in the order they appear in the dump's table of contents, or in the order they appear in the list-file if -L is given. The combination of -o and -r duplicates the sorting done by pg_dump before creating the dump's table of contents, and so it is normally unnecessary to specify it.

-R
--no-reconnect

While restoring an archive, pg_restore typically has to reconnect to the database several times with different user names to set the correct ownership of the created objects. If this is undesirable (e.g., because manual interaction (passwords) would be necessary for each reconnection), this option prevents pg_restore from issuing any reconnection requests. (A connection request while in plain text mode, not connected to a database, is made by putting out a psql \connect command.) However, this option is a rather blunt instrument because it makes pg_restore lose all object ownership information, unless you use the -X use-set-session-authorization option.

-s
--schema-only

Restore only the schema (data definitions), not the data. Sequence values will be reset.

-S username
--superuser=username

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

-t table
--table=table

Restore definition and/or data of named table only.

-T trigger
--trigger=trigger

Restore named trigger only.

-v
--verbose

Specifies verbose mode.

-x
--no-privileges
--no-acl

Prevent restoration of access privileges (grant/revoke commands).

-X use-set-session-authorization
--use-set-session-authorization

Normally, if restoring an archive requires altering the current database user (e.g., to set correct object ownerships), a new connection to the database must be opened, which might require manual interaction (e.g., passwords). If you use the -X use-set-session-authorization option, then pg_restore will instead use the SET SESSION AUTHORIZATION command. This has the same effect, but it requires that the user restoring the archive is a database superuser. This option effectively overrides the -R option.

-X disable-triggers
--disable-triggers

This option is only relevant 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 specify --use-set-session-authorization and run pg_restore as a PostgreSQL superuser.

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

Connect as the given user

-W

Force a password prompt. This should happen automatically if the server requires password authentication.

Environment

PGHOST
PGPORT
PGUSER

Default connection parameters

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.

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.

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.

Examples

To dump a database called mydb that contains large objects to a tar file:

$ pg_dump -Ft -b mydb > db.tar

To reload this database (with large objects) to an existing database called newdb:

$ pg_restore -d newdb db.tar

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

$ pg_restore -l archive.file > archive.list

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

;
; Archive created at Fri Jul 28 22:28:36 2000
;     dbname: birds
;     TOC Entries: 74
;     Compression: 0
;     Dump Version: 1.4-0
;     Format: CUSTOM
;
;
; Selected TOC Entries:
;
2; 145344 TABLE species postgres
3; 145344 ACL species
4; 145359 TABLE nt_header postgres
5; 145359 ACL nt_header
6; 145402 TABLE species_records postgres
7; 145402 ACL species_records
8; 145416 TABLE ss_old postgres
9; 145416 ACL ss_old
10; 145433 TABLE map_resolutions postgres
11; 145433 ACL map_resolutions
12; 145443 TABLE hs_old postgres
13; 145443 ACL hs_old

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 archive.list archive.file

History

The pg_restore utility first appeared in PostgreSQL 7.1.

See Also

pg_dump, pg_dumpall, psql