Firstly, it is not replacing but using it together with MySQL:
Completely replacing MySQL with MongoDB hasn’t ever been on the table.
Second, the article doesn’t provide the real arguments for using MongoDB and it sounds like coolness factor-based adoption:
I looked over at our Chief Architect, Blake Carlson, said “Hey I wanna use MongoDB for this.” His reply was “Cool.”
We had a new application coming online (Vendor Connect) that had a certain set of requirements — stat tracking with “documenty” data — which seemed like a good candidate for a document store.
I haven’t done any performance testing, but it’s hard to compare apples to apples.
Third, the version mentioned (i.e. 1.0.0) is so old that I’m wondering what happened since then. We’ve already covered usecases in which scaling MongoDB was not as easy as some are expecting.
This post is part of the MongoDB Case Studies series.