Elasticsearch: The Definitive Guide
elastic.co
elastic.co
Also I feel like they could reduce the needs for super great API docs if they had something like a query optimizer so that I don't have to care about the exact way that ES translates my queries into Lucene queries. My favorite bit is how if you permute your filters and queries in the wrong order you end up completely killing your performance (filter then query or query then filter).
https://www.elastic.co/blog/elasticsearch-2.0.0.beta1-coming...
I might be biased towards Manning books, but I find their style and ELI5 wording to be very helpful as an introduction to a subject.
But I can understand the appeal. If you're looking to feel more intimate with the technology from another persons perspective or do not want terrible documentation, this kind of style makes sense I suppose
The best way to learn ES is to set yourself up with a scripting language (python, ruby, etc.) and prototype everything, then apply what you learned to your language of chocie (i.e. Java if the scripting language isn't your language of choice).
That said ELK is great overall and I would still use it for user-facing search, but I think there is still a lot to improve.
It is different in that it provides higher level APIs and distributed functionality on top of Lucene. For example, one Elasticsearch index might contain multiple Lucene indices spread across multiple machines, but your application treats it as a single "index".