figure join the nosql movement top databases ranked by popularity according to db-engines com in march figure shows that with entriesrelational databases still dominate the top at the time this book was writtenand with the coming of newsql we can' count them out yet neo jthe most popular graph databasecan be found at position at the time of writingwith titan at position now that you've seen each of the nosql database typesit' time to get your hands dirty with one of them case studywhat disease is thatit has happened to many of usyou have sudden medical symptoms and the first thing you do is google what disease the symptoms might indicatethen you decide whether it' worth seeing doctor web search engine is okay for thisbut more dedicated database would be better databases like this exist and are fairly advancedthey can be almost virtual version of dr housea brilliant diagnostician in the tv series house but they're built upon well-protected data and not all of it is accessible by the public alsoalthough big pharmaceutical companies and advanced hospitals have access to these virtual doctorsmany general practitioners are still stuck with only their books this information and resource asymmetry is not only sad and dangerousit needn' be there at all if simpledisease-specific search engine were used by all general practitioners in the worldmany medical mistakes could be avoided in this case studyyou'll learn how to build such search engine herealbeit using only fraction of the medical data that is freely accessible to tackle the problemyou'll use modern nosql database called elasticsearch to store the dataand the