NoSQL is a type of database that stores and retrieves data without needing to define its structure first – an alternative to the more rigid relational databases. NoSQL are non tabular, and store data differently than relational tables. It should be noted that NoSQL databases can store relationship data—they just store it differently than relational databases do. That should clear the misconception that NoSQL databases or non-relational databases don’t store relationship data well. Source: MongoDB Site

Types of NoSQL Database

  • Document Databases: They usually pair each key with a complex data structure also known as a document. Examples of NoSQL in this category are MongoDB, Apache CouchDB, Raven DB and others.
  • Key-value stores: In this group, every item in it is stored as a Key-value pair. Examples include Apache Ignite,Redis, Riak, Memcached.
  • Wide-column stores: These store columns of data together. The reason for this that they are optimized for queries over huge datasets. Examples include Cassandra, Hbase, Scylla.
  • Graph stores: They include Neo4j, and AllegroGraph.

Advantages of NoSQL databases

The following are some of the advantages that you will enjoy while using NoSQL databases.

  • They are wonderful at handling large volumes of data at high speed with a scale-out architecture