Synonyms (PDM)

A synonym is an alternative name for various types of objects (table, view, sequence, procedure, function, synonym or database package).

Synonyms are created to:

Mask the name and owner of an object
Provide location transparency for remote objects of a distributed database
Simplify SQL statements for database users

For example, table SALES_DATA is owned by user JWARD. A standard select statement on this table would be:

SELECT * FROM jward.sales_data

The database administrator can create a synonym for this table and owner and call it SALES. In this case, the SQL statement is simplified in the following way:

SELECT * FROM sales

In PowerDesigner synonyms are created for base objects. Base objects support multiple synonyms while each synonym can have only one base object. You can view the synonyms depending on a base object in the Dependencies tab of the base object property sheet. If you delete the base object of a synonym, the synonym is deleted as well.

Note: PowerDesigner supports the generation and reverse-engineering of synonyms. When you reverse-engineer synonyms, the link with the base object is preserved if both objects are reverse engineered and if the base object is displayed before the synonym in the script. You can reverse a synonym without its base object, but then you should define a base object for it.

Creating a Synonym
You can create a synonym from the Model menu.
Synonym Properties
To view or edit a synonym's properties, double-click its Browser or list entry. The property sheet tabs and fields listed here are those available by default, before any customization of the interface by you or an administrator.
Creating a View for a Synonym
You can create views for synonyms in the same way as you create views for tables. The view query displays the content of the object used for the synonym. For example, the ORDERS_PROD_DEPT table has a synonym ORDERS:

Parent topic: Physical Diagrams