Automatic Calculation of Other BO Aggregation

Summary

How to automatically fill BO with another aggregate BO

Content

Hi All,

I have a BO which I need to populate with a count of another BO's specific fields?

BO-A - (100 rows)

Fields: UserName(string), Category(string), ...

BO-B (4 rows of unique categories)

Fields: Category(string), Counter(number)

 

I want to "group-by" all categories from BO-A to appear in Counter field of BO-B.

I tried using a reference field with no success as performed here:

https://www.youtube.com/watch?v=NFKdUyv-Gbs&feature=youtu.be&t=227

Any suggestions?

 

Thanks,

Ziv