2001-03-06
pg_restore
1Applicationpg_restore
Restore a Postgres database from an archive file created by
pg_dumppg_restore -a -c -C -d dbname -f archive-file -F format -i index -l -L contents-file -N -o -r -O -P function-name -R -s -S -t table -T trigger -v -x -h host -p port -U username -W archive-file
Description
pg_restore is a utility for restoring a
Postgres database dumped by
in one of the non-plain-text formats.
The archive files, new with the 7.1 release, contain enough information for
pg_restore to rebuild the database, but 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_dump will
produce the queries necessary to re-generate all user-defined types, functions,
tables, indexes, aggregates, and operators. In addition, all the data is copied
out (in text format for scripts) so that it can be readily copied in again.
pg_restore reads the archive file and outputs the appropriate
SQL in the required order based on the command parameters. Obviously, it can not restore
information that is not present in the dump file; so if the dump is made using the
dump data as INSERTs option, pg_restore will not be able to
load the data using COPY statements.
The most flexible output file format is the custom format (). It allows for
selection and reordering of all archived items, and is compressed by default. The tar
format () is not compressed and it is not possible to reorder
data when loading, but it is otherwise quite flexible.
To reorder the items, it is first necessary to dump the contents of the archive:
$pg_restore archive.file -l > archive.list
This 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
Semi-colons are comment delimiters, 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 archive.file -L archive.list
Options
pg_restore accepts the following command
line arguments. (Long option forms are only available on some platforms.)
archive-name
Specifies the location of the archive file to be restored.
If not specified, and no option is specified, then the standard input is used.
-a--data-only
Restore only the data, no schema (definitions).
-c--clean
Clean (drop) schema prior to create.
-C--create
Include SQL to create the schema.
-d dbname--dbname=dbname
Connect to database dbname and restore
directly into the database. BLOBs can only be restored by using a direct database connection.
-f filename--file=filename
Specify output file for generated script. (Use with the
option.) 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
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
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 index--index=index
Restore definition for named index only.
-l--list
List the contents of the archive. The output of this command can be used with the 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.
-N--orig-order
Restore items in the original dump order. By default pg_dump will dump items in an order convenient
to pg_dump, then save the archive in a modified OID order. This option overrides the OID ordering.
-o--oid-order
Restore items in the OID order. By default pg_dump will dump items in an order convenient
to pg_dump, then save the archive in a modified OID order. This option enforces strict OID ordering.
-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.
-P function-name--function=function-name
Specify a procedure or function to be restored.
-r--rearrange
Restore items in modified OID order. By default pg_dump will dump items in an order convenient
to pg_dump, then save the archive in a modified OID order. Most objects
will be restored in OID order, but some things (e.g., rules and indexes) will be restored at the end of
the process irrespective of their OIDs. This option is the default.
-R--no-reconnect
Prohibit pg_restore from issuing any \connect
statements or reconnecting to the database if directly connected.
-s--schema-only
Restore the schema (definitions), no data. Sequence values will be reset.
-S username--superuser=username
Specify the superuser user name to use when disabling triggers and/or setting ownership of schema elements.
By default, pg_restore will use the current user name if it is a superuser.
-t table--table=table
Restore schema/data for table only.
-T trigger--trigger=trigger
Restore definition of trigger only.
-v--verbose
Specifies verbose mode.
-x--no-acl
Prevent restoration of ACLs (grant/revoke commands).
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
postmaster
is running. If host begins with a slash, it is used
as the directory for the Unix domain socket.
-p port--port=port
Specifies the Internet TCP/IP port or local Unix domain socket file
extension on which the postmaster
is listening for connections. The port number defaults to 5432,
or the value of the PGPORT
environment variable (if set).
-U username
Connect as the given user.
-W
Force a password prompt. This should happen automatically if
the server requires password authentication.
Diagnostics
Connection to database 'template1' failed.
connectDBStart() -- connect() failed: No such file or directory
Is the postmaster running locally
and accepting connections on Unix socket '/tmp/.s.PGSQL.5432'?
pg_restore could not attach to the
postmaster
process on the specified host and port. If you see this message,
ensure that the postmaster
is running on the proper host and that you have specified the proper
port. If your site uses an authentication system, ensure that you
have obtained the required authentication credentials.
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
The limitations of pg_restore are detailed below.
When restoring data to a table, pg_restore emits queries
to disable triggers on user tables before inserting the data then emits queries 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.
pg_restore will not restore BLOBs for a single table. If
an archive contains BLOBs, then all BLOBs will be restored.
See the documentation for details on
limitation of pg_dump.
Examples
To dump a database:
$pg_dump mydb > db.out
To reload this database:
$psql -d database -f db.out
To dump a database called mydb that contains
BLOBs to a tar file:
$pg_dump -Ft -b mydb > db.tar
To reload this database (with BLOBs) to an
existing database called newdb:
$pg_restore -d newdb db.tarSee AlsoPostgreSQL Administrator's Guide