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From couchdb user <>
Subject Re: how to count the number of unique values
Date Sun, 17 Oct 2010 04:00:56 GMT
On Sat, Oct 16, 2010 at 10:41 PM, Anand Chitipothu <> wrote:
> 2010/10/16 Eli Stevens (Gmail) <>:
> I thought about this, but in my case the list of can be very big. I've
> seen subjects with 500K works. I don't think it is a good idea to let
> reduce build such a big list.
> Anand

I'm not sure how often your data will change but how about storing the
list of unique works, etc on a separate database, and then have a map
/ reduce what will give you the number of unique entries based on that
"intermediate" database? Something like a chain map reduce is what I'm
thinking about.

Of course you will have to maintain that other database in sync, and
using the _changes feed could help here.
Let me know if you would need some example of what I'm trying to say.



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