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From Robert Newson <robert.new...@gmail.com>
Subject Re: Map/Reduce Question
Date Fri, 03 Dec 2010 09:41:18 GMT
Matthew,

Your original message implied that you might have duplicates but I
didn't notice that you had documents with the same key but different
contents (and there isn't one in your example).

You can't reduce your way out of that, I think. What you can do instead is;

map:

function(doc) {
  if (doc.foo != '' && (doc.bar != '' || doc.baz != '')) {
    emit([doc.foo, doc.bar, doc.baz], null);
  }
}

reduce:

function(keys, values, rereduce) {
  return null;
}

When queried with group=true, you'll get one row for every unique
combination of foo, bar and baz.

B.




On Thu, Dec 2, 2010 at 11:57 PM, Matthew Woodward <matt@mattwoodward.com> wrote:
> On Thu, Dec 2, 2010 at 3:50 PM, Randall Leeds <randall.leeds@gmail.com>wrote:
>
>> I think you may want to play w the ?group_level query parameter.
>>
>
> Thanks--messed with that but since my keys weren't unique across records it
> didn't seem to make a difference. I'll look back into that though.
>
> --
> Matthew Woodward
> matt@mattwoodward.com
> http://blog.mattwoodward.com
> identi.ca / Twitter: @mpwoodward
>
> Please do not send me proprietary file formats such as Word, PowerPoint,
> etc. as attachments.
> http://www.gnu.org/philosophy/no-word-attachments.html
>

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