pg_restore
Description
pg_restore
is a utility for restoring a 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.
pg_restore
can operate in two modes. If a database name is specified, the archive is restored 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. The 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.
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.
Note: The --ignore-version
option is deprecated and will be removed in a future release.
filename
Specifies the location of the archive file to be restored. If not specified, the standard input is used.
Restore Options
-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 this database and restore directly into this database. The default is to use the PGDATABASE
environment variable setting, or the same name as the current system user.
-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 outfilename | —file=outfilename
Specify output file for generated script, or for the listing when used with -l
. Default is the standard output.
-F t |c | —format=tar | custom
The format of the archive produced by pg_dump. It is not necessary to specify the format, since pg_restore
will determine the format automatically. Format can be either tar
or custom
.
-i | —ignore-version
Note: This option is deprecated and will be removed in a future release.
Ignore database version checks.
-I index | —index=index
Restore definition of named index only.
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 the 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 schema | —schema=schema
Restore only objects that are in the named schema. This can be combined with the 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. The function name must be enclosed in quotes. Be careful to spell the function name and arguments exactly as they appear in the dump file’s table of contents (as shown by the --list
option).
-s | —schema-only
Restore only the schema (data definitions), not the data (table contents). Sequence current values will not be restored, either. (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 deactivating triggers. This is only relevant if --disable-triggers
is used.
Note: Greenplum Database does not support user-defined triggers.
-t table | —table=table
Restore definition and/or data of named table only.
-T trigger | —trigger=trigger
Restore named trigger only.
Note: Greenplum Database does not support user-defined triggers.
-v | —verbose
Specifies verbose mode.
-x | —no-privileges | —no-acl
Prevent restoration of access privileges ( GRANT/REVOKE
commands).
--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 triggers on the tables that you do not want to invoke during data reload. 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 superuser.
Note: Greenplum Database does not support user-defined triggers.
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 when the target database may already contain the desired table contents. Specifying this option prevents duplicate or obsolete data from being loaded. This option is effective only when restoring directly into a database, not when producing SQL script output.
Connection Options
-h host | —host host
The host name of the machine on which the Greenplum master database server is running. If not specified, reads from the environment variable PGHOST
or defaults to localhost.
-p port | —port port
The TCP port on which the Greenplum Database master database server is listening for connections. If not specified, reads from the environment variable PGPORT
or defaults to 5432.
-U username | —username username
The database role name to connect as. If not specified, reads from the environment variable PGUSER
or defaults to the current system role name.
-W | —password
Force a password prompt.
-1 | —single-transaction
Execute the restore as a single transaction. This ensures that either all the commands complete successfully, or no changes are applied.
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:
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 may be left in the wrong state.
pg_restore
will not restore large objects for a single table. If an archive contains large objects, then all large objects will be restored.
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 query planner has useful statistics.
Assume we have dumped a database called mydb
into a custom-format dump file:
To drop the database and recreate it from the dump:
dropdb mydb
pg_restore -C -d template1 db.dump
To reload the dump into a new database called newdb
. Notice there is no -C
, we 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:
The listing file consists of a header and one line for each item, for example,
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
Could be used as input to and would only restore items 10 and 6, in that order:
pg_restore -L db.list db.dump