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Mongoid Collection Snapshot - Great for MapReduce

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Mongoid Collection Snapshot - Great for MapReduce

· Database Zone ·
Free Resource

Download "Why Your MySQL Needs Redis" and discover how to extend your current MySQL or relational database to a Redis database.

Another fine open-source contribution from @aaw, mongoid_collection_snapshot: easy maintenance of collections of processed data in MongoDB with the Mongoid ODM.

 

https://github.com/aaw/mongoid_collection_snapshot


This turned out to be extremely useful in many map-reduce scenarios where we do lengthy computations that output data that is used as a complete and consistent set. For example, calculating average prices across ranges of items (the example in the documentation). Another good use can be for tags stored as arrays of strings – you want to know how many items are tagged with a given entry. We can now take my incremental tag count map-reduce and replace it with a much more trivial implementation that uses this gem.

Read "Developing Apps Using Active-Active Redis Enterprise" and discover the advantages over other active-actve databases.

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