This document provides an introduction to NoSQL databases. It describes NoSQL as non-relational, distributed, open-source databases that are horizontally scalable with no predefined schema. It lists the main types of NoSQL databases as document stores, graph stores, key-value stores, and wide-column stores. The document gives MongoDB as an example of a document database and explains that sharding allows horizontal scaling by storing data records across multiple machines.

1. A N I N T R O D U C T I O N
# N O S Q L
NoSQL

2. What is NoSQL
Next Generation database
Characteristics
 Non-relational
 Distributed
 Open-source
 Horizontally scalable
 No Predefined Schema

3. An example
{
"_id" : { "$oid" : "536ce8d1c25cf6e89fa7deeb"} ,
"name" : "USA" ,
"type" : "country" ,
"count" : "1" ,
"states" : { "1" : "MA" , "2" : "TX" , "3" : "CA"}
}

4. Types of NoSql
 Document databases Similar to Key/Value but with a
major difference that value is a document. Inspired by Lotus
Notes. Example Couch DB, Mongo DB
 Graph stores are used to store information about networks,
such as social connections. Graph stores include Neo4J and
HyperGraphDB.
 Key-value stores are the simplest NoSQL databases. Every
single item in the database is stored as an attribute name (or
"key"), together with its value. Examples are Riak and
Voldemort.
 Wide-column stores such as Cassandra and HBase are
optimized for queries over large datasets, and store columns
of data together, instead of rows. Example Hadoop/ Hbase,
Cassnadra, Level DB (from Google), BigTable

5. Why #nosql
 Dynamic Schema
 Large columns of structured, semi structured data
and unstructured data
 Efficient scale out architecture (Sharding)
 Helps in Agile development

6. SQL Databases No SQL Database
Example Oracle , mysql Mondo DB,
CouchDB, Neo4J
Storage
Model
Rows and tables Key-value. Data
stored as single
document in JSON,
XML
Schemas Static Dynamic
Scaling Vertical &
Horizontal
Horizontal
Transactions Yes Certain levels
Data
Manipulation
Select, Insert ,
Update
Through Object
Oriented API’s
Differences

7. MongoDB
 It is type of Document database
 Written in C++
 Development started in 2007
 Commercial supported and developed by 10Gen
 Supports multiple types of indexing
 In built Sharding

8. What is Sharding
Sharding is the process of storing data records across
multiple machines a.k.a Horizontal Scaling

9. References
 http://nosql-database.org/
 http://www.mongodb.com/nosql-explained
 http://www.slideshare.net/dstainer/introduction-
to-nosql-databases