What is NoSQL and CAP Theorem June 2014 NoSQL Meetup Rahul Jain @rahuldausa
Who am I ?  Software Engineer  7 years of software development experience  Areas of expertise/interest  High traffic web applications  JAVA/J2EE  Big data, NoSQL  Information-Retrieval, Machine learning 2
Agenda • What is NoSQL • CAP Theorem 3
NoSQL Not SQL does not mean
NoSQL Not Only SQL OR Not Relational DatabaseIt means
Why NoSQL • Large Volume of Data • Dynamic Schemas • Auto-sharding • Replication • Horizontally Scalable * Some Operations can be achieved by Enterprise class RDBMS software but with very High cost
Major NoSQL Categories • Document databases • pair each key with a complex data structure known as a document. • MongoDB • Graph databases • store information about networks, such as social connections • Neo4j Contd.
Major NoSQL Categories • Key-Value stores • Every single item in the database is stored as an attribute name (or "key"), • Riak , Voldemort, Redis • Wide-column stores • store data in columns together, instead of row • Google’s Bigtable, Cassandra and HBase
CAP Theorem
CAP Theorem • Consistency – All the servers in the system will have the same data so anyone using the system will get the same copy regardless of which server answers their request. • Availability – The system will always respond to a request (even if it's not the latest data or consistent across the system or just a message saying the system isn't working) • Partition Tolerance – The system continues to operate as a whole even if individual servers fail or can't be reached..
Credit: http://architects.dzone.com/articles/better-explaining-cap-theorem
Choosing AP Credit: https://foundationdb.com/key-value-store/white-papers/the-cap-theorem
Choosing CP Credit: https://foundationdb.com/key-value-store/white-papers/the-cap-theorem Replication allows to add Availability
Finally … SQL Works great, but can’t fit for large dataset NoSQL Works great, but can’t fit for all Use-cases SQL + NoSQL
Thanks! @rahuldausa on twitter and slideshare http://www.linkedin.com/in/rahuldausa Interested in Search/Information Retrieval ? Join us @ http://www.meetup.com/Hyderabad-Apache-Solr-Lucene-Group/ 15

What is NoSQL and CAP Theorem