Epics and Parents and Children, Oh My!

[#1]

In answering a recent question that involved finding other children of the same Epic, I mistakenly suggested using the parentEpic function, when the asker probably only needed to use the parent field.

I also found another interesting and potentially useful function that is named for the renamed Portfolio (fka Advanced Roadmaps, now Plans): portfolioChildIssuesOf.

[Also, I know that Epic Link has been replaced with Parent back in November 2022, but it seems like the parentEpic function still works, although not in the way it is documented.]

Anyways, this is probably best explained in a picture:

So the hierarchy is like this:

• BUG-5 is an Epic
  • BUG-13 is a Task under the BUG-5 Epic
    • BUG-14 is a Sub-task under the BUG-13 Task

What I found interesting is what these different JQL functions/fields return:

parent

parent="BUG-5"

Pretty straight-forward. Show me all tickets whose immediate parent is BUG-5.

portfolioChildIssuesOf

issue in portfolioChildIssuesOf("BUG-5")

So, this one shows you ALL the descendants of BUG-5, so Tasks and Subtasks, or children and grandchildren, if we're continuing this analogy.

I guess this could be useful if you really want to find EVERY issue under an Epic. But what's interesting to me is that while portfolioChildIssuesOf is only mentioned on this page about searching custom fields from Plans, which is a Jira Premium feature, it works for me on a Jira Free plan. (Shhh, don't tell anybody - maybe they'll put it behind a paywall.)

parentEpic

parentEpic="BUG-5"

So this is the weird one that does not match the documentation which says:

Search for issues and sub-tasks that are linked to an epic. 

I mean, yes, it does return issues and sub-tasks, just like portfolioChildIssuesOf, but interestingly, it ALSO returns the Epic itself!

Could this be useful? I mean, sure? To somebody? I'd love to hear your use cases.

(NOTE: I only tested this on Jira Cloud, and as noted, it's a Free instance.)