Oracle Database Tips by Donald Burleson

Administration and Creation of Synonyms

Synonyms are a very powerful feature of Oracle and other SQL-compliant relational database systems. They are used as a database shorthand. They make it possible to shorten the specification of long or complex object names. This is especially useful for shared tables or views. In addition, the use of DATABASE LINKS in synonyms allows transparent access to other databases on other nodes or even other entire systems halfway around the globe.

Synonyms are created using the CREATE SYNONYM command. Synonyms can be either PRIVATE (the default) or PUBLIC. Private synonyms can only be used by the user creating them. You must have a specific grant or one of the special ROLES assigned to you before you can create synonyms. Only users with appropriate privileges (usually DBAs) can create PUBLIC synonyms. Since only the owner can use them, PRIVATE synonyms are more secure.

The simplified format of the CREATE SYNONYM command follows:

See Code Depot

where:  

Synonym. An allowed name. (It cannot be the name of an existing object for this user. For the purposes of uniqueness, the schema name is considered to be a part of the name for an object.) 

Schema.object. An existing table, view, package, procedure, function, Java object, materialized view, other synonym, or sequence name. The schema object cannot be contained in a package. A synonym cannot be created for an object type.

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