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From Wout Mertens <wout.mert...@gmail.com>
Subject Re: map/reduce function question
Date Tue, 28 Apr 2009 11:50:46 GMT
Well I was wrong, a reduce query doesn't show the amount of rows. So  
you'll have to count the number of rows that the view Paul gave  
returns in your application, or you'll have to wait until CouchDB  
gains multiple map+reduce passes.

Wout.

On Apr 28, 2009, at 11:22 AM, Wout Mertens wrote:

> You can cheat: simply get the MR view that Paul gave you with
> group=true and it will tell you the total number of results, which is
> the answer you're looking for. At least, I think so, I can't test now.
>
> If it doesn't, this is yet another case for multi-MR views :)
>
> Wout.
>
> On Tuesday, April 28, 2009, Kevin Wang <javaperl@gmail.com> wrote:
>> Sorry I think I made a mistake stating the problem.
>>
>> I have the following 4 docs:
>>
>> {"name": "foo", "prop": "value1"}
>> {"name": "bar", "prop": "value2"}
>> {"name": "foo", "prop": "value3"}
>> {"name": "bob", "prop": "value4"}
>>
>> How to write the map/reduce functions so that I can get a view  
>> which returns
>> the total number of unique name's?  In this case, the result should  
>> be 3.
>>
>> -- Kevin
>>
>> On Mon, Apr 27, 2009 at 7:32 PM, Kevin Wang <javaperl@gmail.com>  
>> wrote:
>>
>>> Hi All,
>>>
>>> While I am trying to switch my mind to map/reduce model while  
>>> accessing
>>> couchdb data, I found myself struggling.  Here is a simple  
>>> question that you
>>> guys might be able to answer:
>>>
>>> If I have the following set of data in a doc:
>>>
>>> {"name": "foo", "prop": "value1"}
>>> {"name": "bar", "prop": "value2"}
>>> {"name": "foo", "prop": "value3"}
>>> {"name": "bob", "prop": "value4"}
>>>
>>> How to write the map/reduce functions so that I can get a view which
>>> returns the total number of unique name's?  In this case, the  
>>> result should
>>> be 3.
>>>
>>> Thanks!
>>>
>>> -- Kevin
>>>
>>


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