This slide deck tries to give an overview about the consistency options we have today and what we can expect in the future. It's an updated version of slide deck I had uploaded to SlideShare before. Unfortunately, SlideShare removed the option to update a slide deck. Thus, I had to remove the old slide deck and create a new one, even if it actually was just an update.
It starts with examining RDBMS and ACID transactions - especially looking at the fact that "ACID" does not necessarily mean serializablity (what most developers think of if they reason about consistency).
Then it describes the current state of IT affairs concerning Cloud, microservices, NoSQL databases and BASE transactions. It then dives a bit deeper into the topic of polyglot persistence and its challenges by introducing a little "storage dimension model" that may support you in picking the right storage solution that fits your needs. Especially it is pointed out that in the storage world there is no one-size-fits-all solution available and especially that NoSQL databases - definitely having their sweet spots where they shine - are no drop-in replacement for a RDBMS.
Afterwards, BASE transactions are examined in more detail - especially the fact that their trade-off for providing us with better availability and scalability is a very hard programming model. To underline that point the typical types of inconsistencies that you often will see with BASE transactions are sketched on what you need to do on the application level in order to cope with them.
In the third section, a peek into the future is made by looking at some current research results that will eventually find their way into commercial application development. The core observation is that even in highly available systems there are a lot of options regarding consistency. Yet, most of those options require to reason about consistency explicitly on the application level and no longer solely on the read/write level of the underlying data stores - including building explicit consistency support into the application.
In the last section, some recommendation for our daily work are given that can be derived from the former sections.
As always the voice track is missing, but hopefully it will give you a few helpful pointers, though. Especially, at the end a lot of references to computer science papers are included that this slide deck is based on.