.. _view_dialog:

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The View Dialog
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Use the *View* dialog to define a view. The view is not physically materialized; the query is executed each time the view is referenced in a query.

The *View* dialog organizes the development of a View through the following dialog tabs: *General*, *Definition*, and *Security*". The *SQL* tab displays the SQL code generated by dialog selections. 
 
Click the *General* tab to begin.

.. image:: images/view_general.png

Use the fields in the *General* tab to identify a view:

* Use the *Name* field to add a descriptive name for the view. The name of the view must be distinct from the name of any other view, table, sequence, index or foreign table in the same schema. The name will be displayed in the *pgAdmin* tree control.
* Use the drop-down listbox next to *Owner* to select the role that will own the view.
* If applicable, select the name of the schema in which the view will reside from the drop-down listbox in the *Schema* field. 
* Store notes about the view in the *Comments* field.

Click the *Definition* tab to continue.

.. image:: images/view_definition.png

Use the fields in the *Definition* tab to define properties of the view:

* Set the *Security Barrier* switch to *Yes* to indicate that the view is to act as a security barrier.  For more information about defining and using a security barrier rule, see Section 38.5 of the PostgreSQL documentation.
* Use the drop-down listbox next to *Check options* to select from *No*, *Local* or *Cascaded*. 
   The *Local* option specifies that new rows are only checked against the conditions defined in the view. Any conditions defined on underlying base views are not checked (unless you specify the CHECK OPTION).
   The *Cascaded* option specifies new rows are checked against the conditions of the view and all underlying base views.    
* Use the workspace in the *Definition* field to write a query to create a view.

Click the *Security* tab to continue.

.. image:: images/view_security.png

Use the *Security* tab to assign privileges and define security labels.  

Use the *Privileges* panel to assign privileges to a role. Click the *Add* icon (+) to set privileges for the view:

* Select the name of the role that will be granted privileges from the drop-down listbox in the *Grantee* field.
* Click inside the *Privileges* field. Check the boxes to the left of one or more privileges to grant the selected privilege to the specified user.
* Select the name of a role with sufficient privileges to grant privileges on the view from the drop-down listbox in the *Grantor* field. The default grantor is the owner of the database.

Click the *Add* icon (+) to assign additional privileges; to discard a privilege, click the trash icon to the left of the row and confirm deletion in the *Delete Row* popup.

Use the *Security Labels* panel to define security labels applied to the view. Click the *Add* icon (+) to add each security label selection: 

* Specify a security label provider in the *Provider* field. The named provider must be loaded and must consent to the proposed labeling operation.
* Specify a a security label in the *Security Label* field. The meaning of a given label is at the discretion of the label provider. PostgreSQL places no restrictions on whether or how a label provider must interpret security labels; it merely provides a mechanism for storing them. 

Click the *Add* icon (+) to assign additional security labels; to discard a security label, click the trash icon to the left of the row and confirm deletion in the *Delete Row* popup.

Click the *SQL* tab to continue.

Your entries in the *View* 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 *View* dialog: 

.. image:: images/view_sql.png

The example shown demonstrates creating a view named *distributor_codes* that includes the content of the *code* column from the *distributors* table.  
 
* 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.



