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From Paul Davis <paul.joseph.da...@gmail.com>
Subject Re: View Intersections
Date Sat, 11 Apr 2009 02:26:25 GMT
On Fri, Apr 10, 2009 at 8:51 PM, kowsik <kowsik@gmail.com> wrote:
> IMHO, the need for view intersections will go away once we have
> parallel map/reduce to the point where _temp_views's are fast!
>
> K.
>

The lower bound for view generation is disk I/O. Temp views will never
be fast enough for production.

HTH,
Paul Davis

> On Fri, Apr 10, 2009 at 10:04 AM, Wout Mertens <wout.mertens@gmail.com> wrote:
>>
>> On Apr 10, 2009, at 11:46 AM, Sho Fukamachi wrote:
>>
>>> the obvious followup question to those examples is "well, how do I find a
>>> document with all of (n) tags?".
>>
>> How about this algorithm. Needed: tagcount view and document-by-tag view
>>
>> - given a list of tags that the document should have
>> - find the tag that has the lowest document count with the tagcount view
>> - request all documents with that tag through the document-by-tag view
>> - filter manually on documents that match
>>
>> If that would mean too many documents, make a view that emits all
>> combinations of 2 tags a document has, that way you filter by that much
>> more.
>>
>> It would be neat if one could post a temporary view that runs against a
>> subset of the output of a real view. That way the viewserver farm could do
>> the filtering...
>>
>> Wout.
>>
>

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