nosql - Are there any other databases that use Map-Reduce for queries like CouchDB? -

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after learning couchdb , map-reduce queries i've become enthusiastic them, dislike couch's revision , conflict model. there other, 'lighter' nosql databases support using map-reduce query data?

i don't mean in sense mongodb it. mean 1 efficiently it's primary (or @ least first class) means of running query.

the closest thing i've been able find an abstraction layer on top of leveldb.


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