Key-Value stores

To finish the posts about different kind of storage mechanisms I would like to introduce you to the Key-Value datastore.
A key-value datastore is nothing more than a BIG hash table that is able to persist the data in the disk. So why is it interesting? Why would it count as a remarkable datastore?

For sure it is not a new technology or even a new concept, but your Google friends brought it to light doing map reduced processing over key-value datastores. This kind of store is easy to persist, easy to distribute over many nodes (ok there is a lot of technology behind it, but still easier and faster than a relational Database).

I know that it looks like a geek subject, but if you think about the kind of applications that you have, you will find something that will fit in this concept, and maybe you are using relational databases and a lot of tricks for that.

For the moment I would just like to make a note about this subject, but for sure I will return to comment about it (maybe with some examples).

For the time, if you are interested in it, please refer to these projects:
- Keyspace : the whitepapers of this projects give you good idea how it works and where you can apply it;
- Voldemort : a promising datastore (used by linkedin).
- Richard Jones had made a nice post with comments about key-value datastores, much deeper than this one. Please pay a visit really good reference about the subject: http://www.metabrew.com/article/anti-rdbms-a-list-of-distributed-key-value-stores/.


Hope it could trigger some lights for you as it had for me :-)