Redmine

Hi guys !
I recently starts to use redmine to my daily work and i noted a "possible mistake" in the calculation of the "Total Time Spend" in a Parent task.
But only when shows in a Custom query.

For Exemple:

I have a Parent task #1 and other two subtasks (Sub #1 and Sub #2) as shown below:

Parent task # 1 - Spend time = 1h
Subtask # 1 - Spend time = 4h (photo 2)
Subtask # 2 - Spend time = 2H (photo 3)

The total time spent in the parent task is 7h as shown in photo 1. The spend time of the subtasks is 4h and 2h according the photos 2 and 3.

The calculation "error" occurs when I create a "custom query" to show spend time from versions (photo 4).

The query shows only 1h spent in the Parent Task. It is normal ? Im doing something wrong ?

My objective in the future is hide sub tasks from my custom query. If I do this, the parent task # 1 will show only 1h spent (photo 5), when the "correct" value is 7h.

This is really a error in the calculation or this is the correct form of the redmine to calculate the spend time ?

Thank you in advance.

Alex