How do we create a service with port number defined for a progress database. Do we have any documentation on how to perform the same ?
It simply depends on how you start the database.
>proserv -S 50000 ...
You don't need to create in the services file.
To connect to the database you do so using one of the openddge clients or sql clients.
>prowin32.exe -db -S 50000.
What is the advantage we get when we mention it in the services file as a service instead of using the port number ?
The -S parameter accepts either a service name or a service port number. If you use a service name, then the service name must be defined in the appropriate file based on the OS.
It is up to you to determine what best fits your environment.
It's the same advantage you get in any application that uses TCP or UDP: you can re-use a consistent, predictable application configuration on different machines that implement different network services. It also means that a local client can be correctly configured to connect to your service without even knowing the port number.