Roll up field to other entity

Question

I'm very new to dynamics crm, so I'm sorry if the question is a little bit basic.

I created solution. and added 2 entities - questions&answers.

In questions I've 2 roll up fields, one for the average of all the grade fields in answers entity, and the other for calculate how many answers there are to a question.

How can I create the roll up fields? when I click edit, the Realted entity and the Aggreation fields are empty, and I can't add them nothing.

Answer 1

Considering your setup something like below.

Question(Entity) has many Answers(Entity) i.e 1:N relationship. You could have your relationship as N:1 or N:N as well, Provided you have relationship between Question and Answer entity.