NoSQL databases offer data storage and retrieval that is modelled differently to “traditional” relational databases. NoSQL databases typically focus more on horizontal scaling, eventual consistency, speed and flexibility and is used commonly for big data and real-time streaming applications. NoSQL is often described as a BASE system (Basically Available, Soft state, Eventual consistency) as opposed to SQL/relational which typically focus on ACID (Atomicity, Consistency, Isolation, Durability). Common NoSQL data structures include key-value pair, wide column, graph and document.
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