Transcript File - Data Warehousing and Data Mining by Gopinath N

DATA WAREHOUSING AND DATA MINING
BY
N.GOPINATH
AP/CSE
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

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

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.
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.


Characteristics of data warehousing
 Subject
oriented
 Integrated
 Time variant (time series)
 Nonvolatile
 Web based
 Relational/multidimensional
 Client/server
 Real-time
 Include metadata
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

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
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

Thank you