Friday, April 12, 2019

Introduction To Data Warehousing

Data ware housing concepts are most important in understanding IT work environment. Actually what is data ware housing ? How does it works ? Lets start understanding it.

When a business starts it will store all the financial data for the future analysis purpose. After some time it becomes difficulty in handling huge amount of data or historical data.
So in order to handle this all the data is stored or moved to a particular place and that place is called as "data warehouse" and that process is called as "data warehousing".

When all the business data is stored with Organization for period of time and this system is called as "OLTP" or "Online Transaction Processing". Later on when it is moved by ETL process is called "OLAP" or "Online Analytical Processing".

OLTP is real time data and it is stored for short time (also know as Database)
OLAP is Historical data used for analytical purpose (also know as Data warehouse)

All this process of moving data is done with an ETL tools. And one of the best tools available in the market is "Informatica Power center".




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