[Lens] Formula: Specify grouping dimensions for time series functions

[flash1293]

Moving average, cumulative sum etc. always group by all bucket dimensions except for the first time dimension. This is a good default, but there are use cases for other groupings.

As described for overall metrics (#94597), it should be possible to specify the columns to group by.

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)

[ghudgins]

could be related to this request on XY #62385

[ghudgins]

from elastic community on slack:

I want to add into columns representing the year (I have a field "year"). When I do that what I expect is that percentages [calculated via overall sum are] now are being calculated in the scope of that year (not over the all the documents), but it is not the case.

[flash1293]

+1 via #125377

[flash1293]

+1

Looking to create formulas based on columns. As far as I know, the functions that we have are based on rows. Do we have any functions that perform such operations?

[markov00]

Closing this because it's not planned to be resolved in the foreseeable future. It will be tracked in our Icebox and will be re-opened if our priorities change. Feel free to re-open if you think it should be melted sooner.