NoSQL Databases Types

There are 4 basic types of NoSQL databases:
  1. Key-Value Store – Every single item in the database is stored as an attribute name (or 'key'), together with its value. (Riak, DynamoDB)
  2. Document-based Store - It stores documents made up of tagged elements. Documents can contain many different key-value pairs, or key-array pairs, or even nested documents.(MongoDB, CouchDB)
  3. Column-based Store - Each storage block contains data from only one column (HBase, Cassandra)
  4. Graph-based - Used to store information about networks of data, such as social connections. (Neo4J, Giraph)



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