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From Seledkin Vyacheslav <viacheslav.seled...@avicomp.com>
Subject RE: RE: How to create view to count number of unique values from documents .... ?
Date Fri, 16 Jan 2009 11:34:35 GMT

Thanks for reply, Chris but you gave me no ansver. Please read my question
carefully. I don't want to find how many times any particular tag are encountered across the
documents, but how many unique tags are in documents.
The documented example only gives me ability to request and count the number of rows in ansver
on the client, it is not acceptable because of huge amount of data.

> The documented example is the way to do it.  It's really slow to
> generate the view the first time, but as you add documents it will
> only need to regenerate the index for those new documents.

> Chris

>> On Thu, Jan 15, 2009 at 2:56 AM, Viacheslav Seledkin
>> After reading all docs I think it is not trivial. The task itself: I have
>> documents with fields
>> ..............
>> doc(N) = {
>> ...
>> tag:"y",
>> tag:"o",
>> tag:"b",
>> tag:"b",
>> tag:"v",
>> tag:"r",
>> ............
>> }
>>
>> doc(N+1) = {
>> ...
>> tag:"a",
>> tag:"b",
>> tag:"t",
>> tag:"b",
>> tag:"u",
>> tag:"r",
>> ...
>> }
>>
>> doc(N+2)= {
>> ...
>> tag:"t",
>> tag:"m",
>> tag:"i",
>> tag:"b",
>> tag:"l",
>> tag:"z",
>> ...........
>> }
>> .............
>> and so on...
>>
>> How to create a view that allows to get number of unique tags throught
>> various range of some keys.
>> i.e
>> ..
>> emit(keyN1,"y") - from document doc(N)
>> emit(keyN2,"o") - from document doc(N)
>> ....
>> emit(key(N+2),"z") - from document doc(N+2)
>> ..
>>
>> and view request
>> http://.../_view/?startkey=someStartKey&endkey=someEndKey
>> gives me something like
>>
>> {"rows":[{"key":null,"value":12}]}????
>>
>> Of course i can use documented example with emit("y",1) and
>> reduce()(return
>> sum(values);) and count the number of rows returned to the client but i >>
have
>> many thousands of tags and it is not effective. Any help appreciated.
>>
>>

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