IT (4): Databases (CouchDB, Storm))........

As big data arrives, databases have become a critical part of the data storage and mining.
Common databases: CouchDB,
Database management systems: Relational Database Management System (RDBMS), NoSQL

RDBMS (table based) : MS SQL server, Oracle, IBM DB2, MySQL
NoSQL (key-value, colun and documents based): Cassandra, DynamoDB, BigTable, MongoDB, CouchDB
These two systems vary in their architecture, data handling. NoSQL
------------------------------------------------------------------
Creation, deletion, updating, installation are part of database technology.
------------------------------------------------------------------
Oracle
When Oracle is running in your environment, you need some DBA tasks, like exporting data from the Oracle database. Oracle’s exp utility, it is very easy to dump data from database.
Connect to DB in exp utility
Export (full database; one or more specific Schemas/Users; one or more specific Tables; all objects in a Tablespac
exp
ls -l expdat.dmp

CouchDB
Its written in Erlang language and now operated by Apache software
Its a document store database of NoSQL
JSON to store data, javascript to mine data, HTTP for API
API is RESTful HTTP API
Communication with HTTP protocol using GET (get a particular item), HEAD (to find only header of an item), POST (to upload data), PUT (create new items), DELETE (remove items), COPY (copy items)
Interaction with CouchDB with curl utility and Futon to create, delete and update databases and documents
#Communicating with the database
curl http://127.0.0.1:5984/

#Get list of databases

curl -X GET http://127.0.0.1:5984/_all_dbs

#Create a new  database

curl -X PUT http://127.0.0.1:5984/new_database

#To check if the database is created

curl -X GET http://127.0.0.1:5984/_all_dbs

#To get information of the newly created database

curl -X GET http://127.0.0.1:5984/new_database

Futon  is web-based interface of CouchDB for database and documents handling.

#To create database using Futon

http://127.0.0.1:5984/_utils/

#Creating a Document using curl

#Document is Field-value separated by colon closed in braces

curl -X PUT http://127.0.0.1:5984/database_ name/"id" -d ' { document} '

curl -X PUT http://127.0.0.1:5984/database_ name/"01" -d ' 

{ Name : Carl,   Age : 32,    Job : Artist,    City: Paris} '

#Response of the database as 'ok', 'id', 'rev'

#Verifying the Document using curl

curl -X GET http://127.0.0.1:5984/database_ name/01

Storm

Apache Storm is a free and open source distributed realtime computation system. 

Storm makes it easy to reliably process unbounded streams of data.

Storm can be used with any programming language.

Its usage include realtime analytics, online machine learning, continuous computation.

Its fast as over a million tuples can be processed per second per node.