Advanced Database Systems

What is Data Warehousing?

� A data warehouse can be defined as

follows:

� subject oriented

� integrated

� time-variant

� nonvolatile

* Property of STIPage 1 of 8

Data Warehousing

� It is a collection of data in support of

management decision-making process.

Advanced Database Systems

Benefits of Data Warehousing

� Data warehousing is intended to support

reporting and analysis of data.

� Here are the benefits as follows:

� Potential High Returns on Investment

� Competitive Advantage

Increased Productivity of Corporate

* Property of STIPage 2 of 8

Data Warehousing

� Increased Productivity of Corporate

Decision Makers

Advanced Database Systems

Problems of Data Warehousing

� Here are some problems associated with

developing and maintaining a data

warehouse as follows:

� Underestimation of Resources for Data

Loading

� Hidden Problems with Source Systems

� Required Data not Captured

* Property of STIPage 3 of 8

Data Warehousing

� Required Data not Captured

� Increased End User Demands

� Data Homogenization

� High Demand for Resources

� Data Ownership

� High Maintenance

� Long Duration Projects

� Complexity of Integration

Advanced Database Systems

Data Warehouse Architecture

* Property of STIPage 4 of 8

Data Warehousing

Advanced Database Systems

Data Warehouse Architecture

� Operational Data Store

� A repository of current and integrated

operational data used for analysis

� Load Manager

� Performs all the operations associated with

the extraction and loading of data into the

* Property of STIPage 5 of 8

Data Warehousing

the extraction and loading of data into the

warehouse

Advanced Database Systems

Data Warehouse Architecture

� Warehouse Manager

� Performs all the operations associated with

the management of data in the warehouse

� Query Manager

� Performs all the operations associated with

the management of user queries

* Property of STIPage 6 of 8

Data Warehousing

the management of user queries

Advanced Database Systems

Data Warehouse Architecture

� Detailed Data

� The area of the warehouse which stores all

the detailed data in the database schema

� Lightly and Highly Summarized Data

� The area of the warehouse which stores all

the predefined lightly and highly

* Property of STIPage 7 of 8

Data Warehousing

the predefined lightly and highly

summarized data generated by the

warehouse manager

Advanced Database Systems

Data Warehouse Architecture

� Archive/Backup Data

� The area of the warehouse where detailed

and summarized data are stored for the

purpose of archiving and backup

� Metadata

The area of the warehouse where all the

* Property of STIPage 8 of 8

Data Warehousing

� The area of the warehouse where all the

metadata (data about data) definitions are

stored

� End-User Access Tools

� These tools are used to interact with the

data warehouse to obtain information