CouchDB vs Voldemort

• It can replicate and sync with web browsers via PouchDB. This lets you keep a synced copy of your database on the client-side, which offers much faster data access than continuous HTTP requests would allow, and enables offline usage.
• Simple Map/Reduce support. The M/R system lets you process terabytes of documents in parallel, save the results, and only need to reprocess documents that have changed on subsequent updates. While not as powerful as Hadoop, it is an easy to use query system that's hard to screw up.
• Sharding and Clustering support. As of CouchDB 2.0, it supports clustering and sharding of documents between instances without needing a load balancer to determine where requests should go.
• Master to Master replication lets you clone, continuously backup, and listen for changes through the replication protocol, even over unreliable WAN links.

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• NoSQL DB can become a challenge for seasoned RDBMS users.
• The map-reduce paradigm can be very demanding for first-time users.
• JSON format documents with Key-Value pairs are somewhat verbose and consume more storage.

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• It has saved us hours and hours of coding.
• It is has taught us a new way to look at things.
• It has taught us patience as the first few weeks with CouchDB were not pleasant. It was not easy to pick up like MongoDB.

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