CONNECT_DATA

The portion of the connect descriptor that defines the destination database service name or Oracle System Identifier (SID). In the following example, SERVICE_NAME specifies a database service called sales.us.acme.com:

 
   (description=  
    (address=(protocol=tcp)(host=sales-pc)(port=1521))
    (connect_data=
     (service_name=sales.us.acme.com)))