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From Alain RODRIGUEZ <>
Subject Re: Dimensional SUM, COUNT, & DISTINCT in C* (replacing Acunu)
Date Wed, 18 Dec 2013 10:13:09 GMT
Hi, this would indeed be much appreciated by a lot of people.

There is this issue, existing about this subject

Maybe could you help commiters there.

Hope this will be usefull to you.

Please let us know when you find a way to do these operations.


2013/12/18 Brian O'Neill <>

> We are seeking to replace Acunu in our technology stack / platform.  It is
> the only component in our stack that is not open source.
> In preparation, over the last few weeks I’ve migrated Virgil to CQL.   The
> vision is that Virgil could receive a REST request to upsert/delete data
> (hierarchical JSON to support collections).  Virgil would lookup the
> dimensions/aggregations for that table, add the key to the pertinent
> dimensional tables (e.g. DISTINCT), incorporate values into aggregations
> (e.g. SUMs) and increment/decrement relevant counters (COUNT).  (using
> additional CF’s)
> This seems straight-forward, but appears to require a read-before-write.
>  (e.g. read the current value of a SUM, incorporate the new value, then use
> the lightweight transactions of C* 2.0 to conditionally update the value.)
> Before I go down this path, I was wondering if anyone is designing/working
> on the same, perhaps at a lower level?  (CQL?)
> Is there any intent to support aggregations/filters (COUNT, SUM, DISTINCT,
> etc) at the CQL level?  If so, is there a preliminary design?
> I can see a lower-level approach, which would leverage the commit logs
> (and mem/sstables) and perform the aggregation during read-operations (and
> flush/compaction).
> thoughts?  i'm open to all ideas.
> -brian
> --
> Brian ONeill
> Chief Architect, Health Market Science (
> mobile:215.588.6024
> blog:
> twitter: @boneill42

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