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NoSQL Not Only SQL. Edel Sherratt. What is NoSQL ?. Not Only SQL L arge volumes of data No schema Partition tolerance – scale by adding more commodity servers Various data models Various languages Eventual consistency. Some NoSQL database systems. Oracle NoSQL Database
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NoSQLNot Only SQL Edel Sherratt
What is NoSQL? • Not Only SQL • Large volumes of data • No schema • Partition tolerance – scale by adding more commodity servers • Various data models • Various languages • Eventual consistency
Some NoSQL database systems • Oracle NoSQL Database • Apache Cassandra • Apache CouchDB • Apache HBase • mongoDB • Google Bigtable • Redis • Riak • Neo4j • FlockDB • MarkLogic
NoSQL users and applications • adform, digital advertising • Iovation, fraud prevention • IBM, email client back-end • HP, music streaming • Many, many more
National Library of Wales Welsh newspapers online • January 2013 Hacathon • http://hacathonwiki.llgc.org.uk/w/index.php/Main_Page • Data documentation, mentions couchdb: • http://hacathonwiki.llgc.org.uk/w/index.php/Simple_introduction_to_the_data • http://hacathonwiki.llgc.org.uk/w/index.php/ApiDocumentation • Current public interface: • http://www.llgc.org.uk/index.php?id=4723
Some advantages of NoSQL • Scale using clusters of commodity hardware rather than specialist servers • Handle larger volumes of data and higher transaction rates than rdbms • Less need for database administrators • Lower startup costs • Lower expansion costs • Few, if any data model restrictions
Some disadvantages • NoSQL immaturity means expert support scarce • Many data manipulation languages • reduces portability of queries • reduces transferability of skills • No schema, reduces database maintainability • No normalization challenges consistency • Whole document emphasis challenges analysis of data sets
Summary • Characteristics of NoSQL • Some NoSQL databases • Advantages and disadvantages