Document Oriented DatabasesA document database is designed to store semi-structured data as documents, typically in JSON or XML format.At a collection level, this allows for putting together a diverse set of documents into a single collection. Document databases allow indexing of documents on the basis of not only its …
Document Oriented Databases
A document database is designed to store semi-structured data as documents, typically in JSON or XML format.At a collection level, this allows for putting together a diverse set of documents into a single collection. Document databases allow indexing of documents on the basis of not only its primary identifier but also its properties
The most popular document databases are CouchDB, MongoDB,Elastic,Azure Document DB and IBM cloudant NoSQL databases.etc
Graph Based Databases
A graph database stores vertices and directed links called edges. Graphs can be built on relational (SQL) and non-relational (NoSQL) databases. By definition, a graph database is any storage system that provides index-free adjacency. This means that every element contains a direct pointer to its adjacent element and no index lookups are necessary. Neo4j,infinite Graph Hyper GraphDB and GraphDB etc. is most popular Graph Databases.
Column Based Databases
Column-oriented Database is a database management system that stores data tables as columns rather than as rows. It avoids consuming space when storing nulls by simply not storing a column when a value doesn’t exist for that column.
Hbase and Cassandra is most popular columnar databases .Most data warehouses will be stored in a columnar fashion.
One of the main benefits of a columnar database is that data can be highly compressed allowing columnar operations — like aggregate function MIN, MAX, SUM, COUNT and AVG— to be performed very rapidly. Another benefit is that because a column-based DBMS is self-indexing, it uses less disk space than a relational database management system (RDBMS) containing the same data.
Key Value Databases
The key of a key/value pair is a unique value in the set and can be easily looked up to access the data. In-memory caching improves application performance by storing critical pieces of data in memory for low-latency access. Cached information may include the results of I/O-intensive database queries or the results of computationally-intensive calculations. A simple, yet powerful, key/value store is Oracle’s Berkeley DB.