1. Data Warehousing and Data Mining By N.Gopinath AP/CSE
For ppt and Notes refer :

2. Learning Objective
Understand the basic definitions and concepts of data warehouses
Describe data warehouse architectures (high level).
Describe the processes used in developing and managing data warehouses
Explain data warehousing operations
Explain the role of data warehouses in decision support

3. Contd…
Explain data integration and the extraction, transformation, and load (ETL) processes
Describe real-time (active) data warehousing
Understand data warehouse administration and security issues

4. Data warehousing definition
Data warehousing is a Subject oriented, integrated, time variant and non-volatile collection of data in support of management’s decision making process.

5. Contd…
Subject Oriented: Data that gives information about a particular subject instead of about a company's ongoing operations.
Integrated: Data that is gathered into the data warehouse from a variety of sources and merged into a coherent whole.
Time-variant: All data in the data warehouse is identified with a particular time period.
Non-volatile: Data is stable in a data warehouse. More data is added but data is never removed.

6. Characteristics of data warehousing
Subject oriented
Integrated
Time variant (time series)
Nonvolatile
Web based
Relational/multidimensional
Client/server
Real-time
Include metadata

7. Some definitions and Concepts
Data mart
A departmental data warehouse that stores only relevant data
Dependent data mart
A subset that is created directly from a data warehouse
Independent data mart
A small data warehouse designed for a strategic business unit or a department

8. Contd… Operational data stores (ODS)
A type of database often used as an interim (Used for a particular period of time) area for a data warehouse, especially for customer information files
Enterprise data warehouse (EDW)
A technology that provides a vehicle for pushing data from source systems into a data warehouse
Metadata
Data about data. In a data warehouse, metadata describe the contents of a data warehouse and the manner of its use

9. Data warehousing process overview
Organizations continuously collect data, information, and knowledge at an increasingly accelerated rate and store them in computerized systems
The number of users needing to access the information continues to increase as a result of improved reliability and availability of network access, especially the Internet

10. Thank you