mysql cluster catching up with cassandra?

Question

I have been recently looking at nosql solutions for our quite big upcoming database and found that cassandra is good but there are very less resources available online about new releases of cassandra and most of the blogs and articles are related to 0.6 version while now it has also implemented support for hadoop and hive. While on the other hand mysql cluster version is also specifically made to run on horizontal scaled setup using commodity servers.

As we are used to relational model for years and moving to cassandra will need decompiling of brain while the product is still not very mature and community is not also that big to respond quickly to any particular problem I have checked datastax(on of the professional support providers) website and their forums are pretty much dead.

So, how to compare mysql cluster vs cassandra while putting relational and non-relational comparison put aside?

Though cassandra is schema less but still it provies pretty much tabular features like super colum and sub column too so record can be searched from multiple column values.

I have also tried my best to find out how cassandra physically stores updated queries like for a row when a sub column is edited and added quite a big chunk of data then how it physically stores that record and how it accesses that record fast? Because in mysql columns have fixed length allocated so its not a big issue.

Answer 1

Here are some areas where I suspect Cassandra has an advantage:

• Excellent support for larger-than-memory data sets
• Replication: Cassandra supports arbitrary numbers of fully-distributed replicas instead of just partitioned replicas (so, you don't have to have a number of nodes divisible by your replica count in Cassandra, and there are no corner cases to deal with around primary failover), best-in-class support for multiple datacenters, support for synchronous replication as well as asynchronous (important if you're concerned about full durability), and robust self-healing (hinted handoff, read repair, anti-entropy) to make sure you never have to blow away a backup replica and rebuild it from scratch
• No locking during ALTER TABLE, index creation, etc
• Substantially simpler and less error-prone administration (compare http://dev.mysql.com/doc/refman/5.1/en/mysql-cluster-online-add-node.html and http://wiki.apache.org/cassandra/Operations#Bootstrap). In particular, I would call your attention to how many client or other nodes need to be restarted in the Cassandra scenario: none.

To elaborate on the last a little, most people who haven't actually run Cassandra on a multi-node cluster, don't realize just how well Cassandra has been designed for this. For a two minute taste, see Jake Luciani's demo.