Summarizing historic data over past n months

[vivekrsharma]

Currently, we've a new table for every month's data. This works really well for the monthly queries. However we would like the ability to query data over past 3-4 months.

Union is one way to aggregate data across tables in Athena. But that is very expensive query.

It would be very nice to have a historic table that maintains data for past n months.