This is a pretty good summary of what’s going on with non-relational databases right now. There’s definitely some interesting things happening with them, and they are certainly easier to scale.

That being said, I wouldn’t go so far as to say that relational databases are doomed. The advantages of having a data store that automatically enforces integrity constraints, as well as the well-defined standards that allow developers to pick their poison with regards to database without having to alter their code base means that relational databases are going to remain compelling for small to medium projects, as well as large mission-critical applications for quite a while. Combine that with advanced database techniques such as sharding to help distribute relational databases across multiple servers, and I think relational databases will be around for some time to come.

That being said, non-relational databases could very well become the standard for cloud-computing applications, but they will need to settle on some common standard for development before it happens.

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