I know there are a lot of answers on related topics already, but they all seem focused more on overall cumulative totals or on specific scenarios.
At a conceptual level, I've got some simple fields: EventDateTime and Value being pulled from a SQL Server query.
If I want to set up a report that can easily do rolling window calculations on these and ideally be able to flip between different windows and calculations (e.g. rolling 30 days sum of Value, or rolling 6 month count of Value).
What's the cleanest way to set that up from the beginning? Should I bring in a generic Calendar table and join to that in my query so that the EventDateTime is associated with a simpler date field? Should I add some new calculated columns in DAX?
In something like python's pandas library, the rolling sum function makes this super simple.
http://pandas.pydata.org/pandas-docs/version/0.17.0/generated/pandas.rolling_sum.html
In PowerBI, there appear to be a number of messy ways to do it. Any advice on what to start with and what the DAX syntax would be for the proposed solution?