I'm asking about how DSS monitors issues during datasets processing. I see two kinds of potential issues:
Is there a way to monitor / handle those errors in DSS and be notified by email or something ?
They have been developed! You should check the metrics and checks documentation:
Also, there is a hands-on activity at https://knowledge.dataiku.com/latest/courses/automation/metrics-checks-hands-on.html
Another tip that might be useful with the metrics and checks is that you can automate them using scenarios in your project. Here is a good resource from the academy that walks through this: https://academy.dataiku.com/automation-course-1?next=%2Fautomation-course-1%2F668968