.. _extension:

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The Extension Dialog
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Use the *Extension* dialog to install a new extension into the current database. An extension is a collection of SQL objects that add targeted functionality to your Postgres installation.  The *Extension* dialog adds the functionality of an extension to the current database only; you must register the extension in each database that use the extension.  Before you load an extension into a database, you should confirm that any pre-requisite files are installed.

The *Extension* dialog allows you to implement options of the CREATE EXTENSION command through the following dialog tabs: *General* and *Definition*. The *SQL* tab displays the SQL code generated by dialog selections. 

.. image:: images/extension_general.png

Use the fields in the *General* tab to identify an extension:

* Use the drop-down listbox in the *Name* field to select the extension. Each extension must have a unique name.
* Store notes about the extension in the *Comment* field.     

Click the *Definition* tab to continue.

.. image:: images/extension_definition.png

Use the *Definition* tab to select the *Schema* and *Version*:

* Use the drop-down listbox next to *Schema* to select the name of the schema in which to install the extension's objects.  
* Use the drop-down listbox next to *Version* to select the version of the extension to install. 

Click the *SQL* tab to continue.

Your entries in the *Extension* dialog generate a SQL command (see an example below). Use the *SQL* tab for review; revisit or switch tabs to make any changes to the SQL command. 

**Example**

The following is an example of the sql command generated by user selections in the *Extension* dialog: 

.. image:: images/extension_sql.png

The command creates the *chkpass* extension in the *public* schema.  It is version *1.0* of *chkpass*.    
 
* Click the *Info* button (i) to access online help. View context-sensitive help in the *Tabbed browser*, where a new tab displays the PostgreSQL core documentation.
* Click the *Save* button to save work.
* Click the *Cancel* button to exit without saving work.
* Click the *Reset* button to restore configuration parameters.