SQL vs NoSQL

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  • SQL databases are primarily called as Relational Databases (RDBMS). NoSQL databases are primarily called as non-relational, aggregate oriented or distributed databases.
  • SQL databases represent data in form of a table. NoSQL databases represent data in a collection of documents, key-value pairs, graph or wide-column stores.
  • SQL databases are vertically scalable ( scaled by increasing the horse-power of the hardware such as CPU, RAM, SSD etc...). NoSQL databases are horizontally scalable (scaled by increasing the no of database servers).

  • In SQL databases, ACID (Atomicity, Consistency, Isolation and Durability)  is supported. In NoSQL databases, atomicity is only supported with the content of a single aggregate and ACID is not supported when updating across multiple aggregates. NoSQL database follows the  CAP theorem ( Consistency, Availability and Partition tolerance )



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