Service User V/S Proxy user

The service account is the account responsible for starting your window service.
It must be part of the domain administrator and must have access to the database if it is used as part of “Integrated SQLServer Security”

The proxy user is the account used in your Qliksense environment.

This user is responsible for publishing an application on a given stream of your server and thus must have the right to publish on all streams.

For example:
This can be a sa_scheduler, which normally has full rights on all streams or any root admins

You can use a sa_scheduler_1 for qliksense_Dev or sa_scheduler_2 for qliksense_Prod or any user who has the right to publish on all streams.