Cassandra is good when you work with multiple data centre. however, the set up is not easy.
Of course your DBA will say it. Job security!! NoSQL doesn't require a DBA.
for example, in my team, senior engineer (like me) can already handle the data design and programming (actually, it is inside the application already). The infrastructure is handled by hardward Operation guy. So, we don't need DBA to handle schema or normalizing DB. lol DBA is expensive~~~ oh. and scaling can be done by ops guy easily. I can also do that too.
Scale in rdbm is tough. Vertical scaling is expensive in hardware. Horizontal scaling is fxxking complicate and easily to crash.
When I first use Mongo and node.js, my other coworkers have doubt but now, they like Mongo. And I'm bringing people to try node.js.
I recommend you to find a small (very small) project to use in your company. more like caching json data, etc. and try with Mongo. of course, the project is best to be small in scope but high in traffic. Then your PM will be impressed.
I had a launch last year Oct and other PHP servers (15) were over 100% , and MySQL DB servers were crazy. But my 5 node.js servers and a simple replicated MongoDB just sitting calm with no more than 40% usage.
i have done tones of load testing with Node & mongo, and I am very impressed by the performance and the non-blocking nature.
Well. nodejs. I love it. No more php. Of course, doing node is very easily to start, but then tough to master it. Once you master it, it is very easy. The challenge I find is that, instead of sequential programming, you have to think in Event & callback way. Very careful in async nature. Also, node.js is not for junior. You have to have understanding of web technologies and know what you are doing. no lazy programming.
I use tones of library...except socket.io. haahh but I will use it soon. Expressjs is a must to use. I also recommend you to join the node.js facebook or google+ group. 
for mongo, recommend you to join any meet up nearby. I went to the one in Seattle last year. It was good, You will have directly contact with the Mongo creator and engineer.
Trust me or not... Node + Mongo will be the key technology for web development in next 3-5 years. |