CouchDB Strengths

From someone that tried CouchDB and now is evaluating other document databases:

[…] i wanted to verify if some of the features that got me excited in CouchDB (or if any replacement / workarounds) exist

• Can we do serial and “bulk” (several at the same time) submissions in MongoDB?
• Does the query mechanism allow  me to create “views” (where i can easily manipulate the data stored in the DB [i.e. map an attribute called “random” to a JSON key called “GMETRIC[‘my value’]”)?
• Does MongoDB have the ability to create what CouchDB calls “list functions”? (where you can query values from views and then output whatever format you want, directly from the database engine [i.e. a html page]);
• Does MongoDB support “callbacks” or a “changes” API i can use to quickly find out what changed between queries? (what i really need is a mechanism to warn me when something changed - if possible, with information on which attributes changed)?
• Can we easily replicate data across engines? and how well does it handle conflicts in the data? What mechanisms do i have to resolve conflicts? Are there any auto-mechanisms?

Some of these feature do exist in other NoSQL databases. But I’d say the combination of peer-to-peer replication, MapReduce-based views, and its JavaScript application server flavor makes CouchDB unique.

Original title and link: CouchDB Strengths (NoSQL databases © myNoSQL)

via: http://groups.google.com/group/nosql-databases/browse_thread/thread/29dd4f5bf7af3448