Which Aggregate operation use Indexscan?

[steevej (Steeve Juneau)]

@Prof_Monika_Shah

any example of $group or $project that uses index

The above is the same question as the previous one

@Prof_Monika_Shah

I also request you to give me example where $group / $project

And my answer is the same:

@steevej

Sorry, I do not have any example at hand that does not use $match or $sort.

I could try to come up with something but it might involve too much time. I prefer to help on more specific issues like Why COLLSCAN and IXSCAN take same to search data? - #3 by Prof_Monika_Shah for which we are still awaiting some information.