Does Druid compute aggregates during data load?

I was wondering if Druid precomputes the aggregates/updates already computed ones during data loads? Or is this done only when a query is executed.

Thanks,

Ranjit

Ranjit, Druid can optionally roll up data at ingestion time, but I don’t really know what you are asking in terms of precomputing aggregates.

Perhaps reading the white paper may help your understanding of Druid: http://static.druid.io/docs/druid.pdf