How can i summarize the values of custom fields 'X' in another custom field 'X Sum'

Casper_o7t238

I have:

- Parent issue with custom filed 'Team Sum'
- Sub-Tasks with custom field 'Team'

Goal:
I want to summarize the values of the field 'Team' in the custom field 'Team Sum'

 

Additionally:

The custom field 'Team' is a multiple option to choose type.
The field 'Team' values are: 'Front' 'Back' 'QA' etc...

 

Example:

If the Parent has two sub-tasks like:

-Sub-task 1, has the option 'Front' in the field 'Team'
-Sub-task 2, have the option 'Back' in the field 'Team' 

-Custom field 'Team Sum' in the Parent issue has options 'Front' & 'Back' 

Also:
I know how to summarize the story points, and I tried to do the same with the field team, but it didn't work, here is how I did it:

Luka Hummel - codefortynine

Hi Casper,

I'm Luka from codefortynine and I think your use case is an interesting use case for our app Dynamic Custom Fields for Jira.

If you want to avoid the limitations of Jira Automations, you could try to add this Jira expression as a Dynamic Custom Field (You need to replace the custom field ID with the corresponding custom field ID of your instance. You can read more on how to find your custom field ID here):

issue.subtasks?.flatMap(s => s.customfield_10145 != null ? s.customfield_10145 : null).flatMap(f => f != null ? f.value : null).sort()

I have to admit, the expression will not filter out duplicate teams, but that might be possible with some Jira expression magic beyond my comprehension.

Let me know if this would work for you.