Is Apache CouchDB for you?

Sumedha Rubasinghesumedha@apache.org

During this 45 mins..

• What is Apache CouchDB?• Paradigm for modeling data• Demonstration• Features

What CouchDB is NOT..

• Relational Database• SQL• Tabular storage of data• Replacement for relational databases

Different paradigm to model data• Real world application – based on

data in a document• Relational model – maps data into

tables, columns• How about storing the document as it

is !!!

What is CouchDB then?

• Document based database server– Key-value type of storage

• Schema free documents– stored in JSON format– versioning

• REST API• Views• Open source

JSON ?

• Java Script Object Notation• lightweight data storage format based on a

subset of JavaScipt syntax• eg:{

"Subject": "ASF turns 10",

"Author": "ajith",

"PostedDate": "2009-11-20",

"Tags": [

"Apache Software Foundation",

"Open source"

],

"Body": "Recently Apache Software Foundation became 10 years old."

}

Getting started - Installation

• Documentation– http://wiki.apache.org/couchdb/Installation

• Unix-like systems• Mac OS X• Windows

– http://people.virginia.edu/~lmb7s/couch

• Latest source distribution (4th Dec 2009)– 0.10.1

Accessing DB engine - REST

• REST API– curl (unix like OS)– cURL (windows)– GET/PUT/POST/DELETE

Accessing DB engine - Futon

• Futon – Web administration console

Creating a database

• Using REST API• Using Futon

Creating a document

• Futon• REST API

Views

• What is a view?• View in CouchDB context

–A "show" that directly renders a document using JavaScript–MapReduce

• Two types– Permanent view• Indexed• JSON for the view is stored as a design document

– Temporary view• Sent via a HTTP POST• Computed on the fly

• Creating a view using Futon

Programming with CouchDB

• Clients available for many languages– C, C#, Erlang, Java, JavaScript, Perl, PHP,

Python,Ruby & many more..

– http://wiki.apache.org/couchdb/Basics

Sample Java Client (CouchDB4J)• connection

Sample Java Client (CouchDB4J)• Accessing views

CouchApp

• Develop CouchDB applications in a convenient directory structure

• Separate folder for css,js,images,etc...

• To deploy – couchapp push• Change & deploy – couchapp push

Interesting features

• Replication• Versioning• Validation• functions/macros

Important configuration files

• Linux environment• Start up script

– /usr/local/etc/init.d/couchdb start | status | stop

• Configurations (ports,users)– /usr/local/etc/couchdb/local.ini

Samples on the web

http://jchrisa.net/cal/_design/cal/index.html

http://github.com/quirkey/swinger

References

http://wiki.apache.org/couchdb/ http://couchdb.apache.org/

Thank you