hi,
After using Cassandra during development for the past 8 months my team and I
made the decision to switch from Cassandra to MongoDB this morning. I
thought I'd share some thoughts on why we did this and where Cassandra might
benefit from improvement.
- The API is horrible and it produces pointlessly verbose code in
addition to being utterly confusing. EVERYTHING takes a lot of time to
implement with Cassandra, and to be frank, it is incredibly tiring. For
this reason alone I no longer recommend Cassandra. If you want an example,
pick up the O'Reilly book on Cassandra and look through the examples. Such
MASSIVE amounts of code for doing nearly NOTHING. This is ridiculous.
Didn't this strike anyone else as ridiculous? It should have!
- You need to have official client libraries and they need to be
programmer friendly. Yes, I know there are nice people maintaining a
plethora of different libraries, but you need to man up and face reality:
the chaos that is the Cassandra client space is a horrible mess.
- It is buggy and the solution seems to be to just go to the next
release. And the next. And the next. Which would be okay if you could
upgrade all the time, but what to do once you hit production?
I would recommend that everyone interested in improving Cassandra take the
day off, download MongoDB and read
https://github.com/karlseguin/the-little-mongodb-book . Then, while you are
downloading, unpacking, looking at what was in the JAR, reading the book and
pawing through the examples: _pay attention_ to the neatness and the
effortlessness the ease with which you can use MongoDB. Then spend the rest
of the day implementing something on top of it to gain some hacking
experience.
No, really. Do it. This is important. You need to connect with the user
and you need to understand what you ought to be aspiring to.
In any case, thanks for all the effort that went into Cassandra. I will
check back from time to time and perhaps in a year or so it'll be time to
re-evaluate Cassandra.
PS: one last thing. It took us less time to rewrite the DB-interface for
our system to MongoDB AND port over our data than it took to write the
Cassandra implementation.
~G
