How to iterate process with changing filter?

Hi,

Now I am working on an event-log and have a question.

Let me briefly explain my data first.

There are attribute 'Case ID' and each 'Case ID' has several instances. In other words, there are 10 columns with case ID = 1.

So I want to filter the data by its 'Case ID', do some process, and aggregate filtered data again. (like 'for loop' in other language)

I tried 'Loop' operator but it doesn't work as I expected.

If you have any idea, please let me know.

Thanks!