Curt Monash begins his post on “Transparent relational OLTP scale-out” (http://www.dbms2.com/2011/10/23/transparent-relational-oltp-scale-out/) by saying that
There’s a perception that, if you want (relatively) worry-free database scale-out, you need a non-relational/NoSQL strategy. That perception is false.
As more and more people try NoSQL solutions, we are beginning to see that they are not the universal “cure-all” that they are often made out to be. As we show here in this series of blog posts, the CAP Theorem does not say that in “picking two”, you have to entirely forsake the third.
As Daniel Abadi has pointed out in his PACELC blog post (http://dbmsmusings.blogspot.com/2010/04/problems-with-cap-and-yahoos-little.html), a normally running system must make some tradeoffs between latency and consistency and what becomes interesting is how the system reacts to a network partition, does it favor availability or consistency? [...]