Merging is the main missing thing. Drill supports building custom aggregate functions. However, those are currently run in a single thread per grouping. Generally, it is much better to do a two-phased aggregate for custom functions, however the interface doesn't yet support that functionality.
-- Jacques Nadeau CTO and Co-Founder, Dremio On Wed, Sep 23, 2015 at 10:36 AM, Neeraja Rentachintala < [email protected]> wrote: > https://drill.apache.org/docs/developing-an-aggregate-function/ > See the customer aggregate functions are marked as alpha and experimental > usage only. > What features or aspects are missing to make this a 'ready to deploy in > production' capability. > Appreciate response. > > thanks > -Neeraja >
