How to query original estimates on substasks in JQL

Question

Is it possible to have a JQL that filter the sum of original estimates of an issue?

What I would like to show are all those issues that have no original estimates, either on their own or in their subtasks. I understand that for the former original estimates is EMPTY will do, but I am not sure how to query on the subtasks (if any) of the issue.

In Issue Navigator there is a field : sum original estimate (sum as the math symbol) that show the sum of the issues substask, but I don't see how to query it in JQL.

Thanks for your suggestions!

Christian Czaia [Decadis AG] · Accepted Answer

I guess that this won't be possible since JQL only represents the WHERE clause of a query. You'd need a  SUM operation and a GROUP BY I guess...

Cheers Christian