Ryan Angilly:

MongoDB is teh awesome because of a simple query syntax, the ability to shard data across machines easily, and the ability to store files in GridFS while taking advantage of replication & sharding.

Indeed, I think the combination of query syntax and GridFS makes MongoDB unique.

Sharding is supported by many other NoSQL databases and for many of these things are even simpler than having mongod, mongos, etc. Between document databases, CouchDB has recently got BigCouch to address the scaling issue^[1].

As regards querying, one could say that having MapReduce around would get you similar functionality to MongoDB queries. But starting with users’ familiarity with using queries vs programmatic querying and up to execution behavior MongoDB queries and MapReduce are quite different.

Original title and link for this post: 3 Reasons to Use MongoDB (published on the NoSQL blog: myNoSQL)

via: http://ryanangilly.com/post/1091884265/3-reasons-to-use-mongodb

Andrew Glover:

In plain English: sharding without considering the long term consequences is dangerous. Think twice before sharding, especially if you’re considering it before all else. In fact, if you do find yourself considering sharding at the outset, then perhaps you should be looking at a NoSQL alternative to the relational model.

NoSQL databases solution to this is… sharding.

Original title and link for this post: Think Twice Before Sharding (published on the NoSQL blog: myNoSQL)

via: http://thediscoblog.com/2010/08/03/think-twice-before-sharding/

Kristina Chodorow (@kchodorow) explains MongoDB’s sharding implementation (nb still in alpha at the time of this writing):

Sharding is the not-so-revolutionary way that MongoDB scales writes (it’s very similar to techniques described in the Big Table paper and by PNUTS)

Credit Kristina Chodorow

On the same topic of MongoDB sharding, you’ve probably heard already about the “8000000 operations per second with our sharded storage” published on the same blog. I’d like to strongly encourage you once again to check the facts (nb which are almost completely missing this time) before admitting such benchmarks/numbers.

via: http://www.snailinaturtleneck.com/blog/2010/03/30/sharding-with-the-fishes/