NOSQL Implementation and examples Maciej Matuszewski

QUERYING  RESTful interfaces,  SQL, SQL2 (JCR),  Query by example,  SPARQL (RDF Query Language),  UnQL (Unstructured Query Language),  XQuery, XPath,  Other.

DOCUMENT STORE  Documents encapsulate and encode data (or information) in some standard formats or encodings.  Different implementations offer different ways of organizing and/or grouping documents:  Collections,  Tags,  Non-visible Metadata,  Directory hierarchies.

DOCUMENT STORE  Documents are addressed in the database via a unique key that represents that document.  Retrieval of documents based on their contents.  Examples:  eXist,  Apache Jackrabbit (JCR),  MongoDB (BSON – binary JSON),  Apache CouchDB (JSON database).

GRAPH  Elements interconnected with an undetermined number of relations between them.  Any storage system that provides index-free adjacency.  RDF databases.  Examples:  Oracle Spatial and Graph.

KEY–VALUE STORE  Key–value stores allow the application to store its data in a schema-less way.  The data could be stored in a datatype of a programming language or an object.  There is no need for a fixed data model.  Very fast access to data.

KEY–VALUE STORE  Examples:  Eventually ‐ consistent key ‐ value store:  Apache Cassandra,  Dynamo,  Riak.  Key–value cache in RAM:  Redis,  Velocity.

KEY–VALUE STORE  Examples:  Key–value stores on solid state or rotating disk:  MongoDB,  Oracle NoSQL Database,  BigTable.  Ordered key–value stores:  IBM Informix C-ISAM,  Berkeley DB.

OBJECT DATABASE  Information is represented in the form of objects as used in object- oriented programming.  Database is integrated with the programming language – the programmer can maintain consistency within one environment.  Examples:  db4o