Currently a reading query on raw datum returns a single, overall value per stream. For example this request:

/reading?readingType=Difference&localStartDate=2024-01-01&localEndDate=2025-01-01&nodeId=1&sourceId=foo 

will return one value representing the difference between the start and end of 2024.

If aggregation is added, then the query returns one result per aggregation period. For example the following query would return 12 results, one for each month of 2024:

/reading?readingType=Difference&localStartDate=2024-01-01&localEndDate=2025-01-01&nodeId=1&sourceId=foo&aggregation=Month 

This ticket is a request to add support for the latter query returning a single overall result like the former query, but to be based on the specified precomputed aggregation level, under the assumption that can execute more quickly than the original query can over raw data. All things being equal, this new query style should return the same result as the original raw query style, assuming all background aggregation tasks are caught up for the given date range.

So, a new query parameter like overall=ture would "turn on" this new query style, when aggregation is also specified.