Hi experts,
I have a question for the validation rules in Transactions. I have the following hypothetical scenario:
1. I have an activity object, which has a collection of orders and the orders have a collection of products.
2. In the product fields, there is a specific field - e.g. notes that has to be filled by the user
3. I want to create a validation rule in transaction which changes the status of an activity (for example, from open to closed), which checks if all fields for notes (on product object level) are filled in or empty - if they are empty - to display a warning message.
The problem is that when I try to create such rule, I can access only the properties of the Activity object. Am I not doing something right or it is not possible to validate a field, which is a collection of the collection of the object change that needs to be validate?
Hope I explained it clearly 
Regards,
Denis