This book is good for those new to next generation databases that are more applicable to big data, social network, IoT, cloud etc applications. Although this has not gone into the depth of each type ...(Big Table: Cassandra, HBase, MongoDB); (Key-value: DynomoDB, Redis, Riak); (Document JSON/OSO: MangoDB); (Graph: Neo4J); (C-Store: Oracle Exadata, SAP HANA, Vertica) but the content does provide from the perspective of database consistency, sharding, replication, data model, storage and API on these various types. It is a good introduction for IT professionals with RDBMS background as a first step to explore these new types of databases.