As this tweet have put it: twitter.com/martinstraus/status/10...
Using a NoSQL DB just for the sake of it is just a dumb decision, no matter the project.
That goes for every other piece of technology.
The fact that relational technologies fits most use cases even emphasize how such a tweet is just plain wrong.
Like any tool, MongoDB may have use cases, but apart from data caching (by taking into account the data-loss, lack of serious guards and integrity checks, I don't see any interest in MongoDB.
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