.. _backup_dialog:

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The Backup Dialog 
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Using the *pg_dump* utility, *pgAdmin* provides an easy way to create a backup in a plain-text or archived format.  You can then use a client application (like *psql* or the *Query Tool*) to restore a plain-text backup file, or use the Postgres *pg_restore* utility to restore an archived backup. The *pg_dump* utility must have read access to all database objects that you want to back up.

You can backup a single table, a schema, or a complete database. Select the name of the backup source in the *pgAdmin* tree control, right click to open the context menu, and select *Backup...* to open the *Backup* dialog.  The name of the object selected will appear in the dialog title bar.

.. image:: images/backup_general.png

Use the fields in the *General* tab to specify parameters for the backup:

* Enter the name of the backup file in the *Filename* field.  Optionally, select the *Browser* icon (...) to the right to navigate into a directory and select a file that will contain the archive.
* Use the drop-down listbox in the *Format* field to select the format that is best suited for your application.  Each format has advantages and disadvantages: 

   * Select *Custom* to create a custom archive file that you can use with *pg_restore* to create a copy of a database. Custom archive file formats must be restored with *pg_restore*. This format offers the opportunity to select which database objects to restore from the backup file. *Custom* archive format is recommended for medium to large databases as it is compressed by default.

   * Select *Tar* to generate a tar archive file that you can restore with *pg_restore*. The tar format does not support compression.
   
   * Select *Plain* to create a plain-text script file. A plain-text script file contains SQL statements and commands that you can execute at the *psql* command line to recreate the database objects and load the table data.  A plain-text backup file can be edited in a text editor, if desired, before using the *psql* program to restore database objects.  *Plain* format is normally recommended for smaller databases; script dumps are not recommended for blobs. The SQL commands within the script will reconstruct the database to the last saved state of the database.  A plain-text script can be used to reconstruct the database on another machine, or (with modifications) on other architectures.
   
   * Select *Directory* to generate a directory-format archive suitable for use with *pg_restore*.  This file format creates a directory with one file for each table and blob being dumped, plus a *Table of Contents* file describing the dumped objects in a machine-readable format that *pg_restore* can read.  This format is compressed by default.

* Use the *Compression Ratio* field to select a compression level for the backup.  Specify a value of zero to mean use no compression; specify a maximum compression value of 9.  Please note that tar archives do not support compression.  
* Use the *Encoding* drop-down listbox to select the character encoding method that should be used for the archive.
* Use the *Number of Jobs* field (when applicable) to specify the number of tables that will be dumped simultaneously in a parallel backup.
* Use the dropdown listbox next to *Rolename* to specify the role that owns the backup. 

Click the *Dump options* tab to continue. Use the box fields in the *Dump options* tab to provide options for *pg_dump*.

.. image:: images/backup_sections.png

* Move switches in the **Sections** field box to select a portion of the object that will be backed up.  

   * Move the switch next to *Pre-data* to the *Yes* position to include all data definition items not included in the data or post-data item lists.
   
   * Move the switch next to *Data* to the *Yes* position to backup actual table data, large-object contents, and sequence values. 
   
   * Move the switch next to *Post-data* to the *Yes* position to include definitions of indexes, triggers, rules, and constraints other than validated check constraints.
   
.. image:: images/backup_objects.png 

* Move switches in the **Type of objects** field box to specify details about the type of objects that will be backed up.

   * Move the switch next to *Only data* to the *Yes* position to limit the back up to data.
 
   * Move the switch next to *Only schema* to limit the back up to schema-level database objects.
     
   * Move the switch next to *Blobs* to the *No* position to exclude large objects in the backup. 

.. image:: images/backup_do_not_save.png

* Move switches in the **Do not save** field box to select the objects that will not be included in the backup.

   * Move the switch next to *Owner* to the *Yes* position to include commands that set object ownership.

   * Move the switch next to *Privilege* to the *Yes* position to include commands that create access privileges. 

   * Move the switch next to *Tablespace* to the *Yes* position to include tablespaces. 

   * Move the switch next to *Unlogged table data* to the *Yes* position to include the contents of unlogged tables. 

.. image:: images/backup_queries.png

* Move switches in the **Queries** field box to specify the type of statements that should be included in the backup.

   * Move the switch next to *Use Column Inserts* to the *Yes* position to dump the data in the form of INSERT statements and include explicit column names.  Please note: this may make restoration from backup slow.

   * Move the switch next to *Use Insert commands* to the *Yes* position to dump the data in the form of INSERT statements rather than using a COPY command.  Please note: this may make restoration from backup slow.

   * Move the switch next to *Include CREATE DATABASE statement* to the *Yes* position to include a command in the backup that creates a new database when restoring the backup.

   * Move the switch next to *Include DROP DATABASE statement* to the *Yes* position to include a command in the backup that will drop any existing database object with the same name before recreating the object during a backup.

.. image:: images/backup_disable.png

* Move switches in the **Disable** field box to specify the type of statements that should be excluded from the backup.

   * Move the switch next to *Trigger* (active when creating a data-only backup) to the *Yes* position to include commands that will disable triggers on the target table while the data is being loaded.

   * Move the switch next to *$ quoting* to the *Yes* position to enable dollar quoting within function bodies; if disabled, the function body will be quoted using SQL standard string syntax.
   
.. image:: images/backup_miscellaneous.png

* Move switches in the **Miscellaneous** field box to specify miscellaneous backup options.

   * Move the switch next to *With OIDs* to the *Yes* position to include object identifiers as part of the table data for each table.

   * Move the switch next to *Verbose messages* to the *No* position to instruct *pg_dump* to exclude verbose messages.

   * Move the switch next to *Force double quotes on identifiers* to the *Yes* position to force the quoting of all identifiers.

   * Move the switch next to *Use SET SESSION AUTHORIZATION* to the *Yes* position to include a statement that will use a SET SESSION AUTHORIZATION command to determine object ownership (instead of an ALTER OWNER command).

When you’ve specified the details that will be incorporated into the pg_dump command: 

* Click the *Backup* button to build and execute a command that builds a backup based on your selections on the *Backup* dialog. 
* Click the *Cancel* button to exit without saving work.

.. image:: images/backup_messages.png  

If the backup is successful, a popup window will confirm success. Click *Click here for details* on the popup window to launch the *Process Watcher*. The *Process Watcher* logs all the activity associated with the backup and provides additional information for troubleshooting.

.. image:: images/backup_process_watcher.png
   
If the backup is unsuccessful, you can review the error messages returned by the backup command on the *Process Watcher*.