Chapter 1

IBM ICE (Innovation Centre for Education)
Welcome to:
Introduction to Data Warehousing
© Copyright IBM Corporation 2017 9.1

Unit objectives IBM ICE (Innovation Centre for Education)
IBM Power Systems
After completing this unit, you should be able to:
• Know what data warehouse is
• Describe the architecture of data warehouse.
• Explain about data staging and ETL.
• Understand the need of content management.
© Copyright IBM Corporation 2017

An introduction to data warehousing IBM ICE (Innovation Centre for Education)
IBM Power Systems
• Data warehousing is a processing a huge amount of electronic data stored in recent
years and use that data to accomplish goals that go beyond the routine tasks linked
to daily processing.
• A data warehouse is a collection of data that supports decision-making processes. It
provides the following features
–It is subject-oriented.
–It is integrated and consistent.
–It shows its evolution over time and it is not volatile.
• It used to support management
– Decision-making processes
– Business intelligence.
– Emerge the information and knowledge needed to effectively manage the organization.
– Investigation of key challenges and research directions for this discipline.

Data warehouse architectures IBM ICE (Innovation Centre for Education)
IBM Power Systems
The following are the architecture properties of data warehouse system
• Separation
• Scalability
• Extensibility
• Security
• Administerability

IBM Power Systems
The figure represents a Single-Layer Architecture of a Data Warehouse.

IBM Power Systems
• Two-Layer Architecture
• Two-layer architecture to highlight a separation between
– Physically available sources
– Data warehouses, it actually consists of four subsequent data flow stages
• Source layer
• It uses heterogeneous sources of data.
• Data is originally stored to
–Corporate relational databases
–Legacy databases
–Information systems outside the corporate walls.

IBM Power Systems
• Data staging
• Data warehouse layer
• Analysis

IBM Power Systems
The Figure represents the
Data warehouse on a non
single tier architecture.

IBM Power Systems
• Three-Layer Architecture :
• In this architecture, the third layer is the reconciled data layer or operational data
store.
• This layer materializes operational data obtained after integrating and cleansing
source data.
– So those data are integrated, consistent, correct, current, and detailed.
– It sharply separates the problems of source data extraction and integration from those of data
warehouse population.
– Reconciled data leads to more redundancy of operational source data

IBM Power Systems
Data Staging and ETL
• ETL consists of four separate phases:
– extraction (or capture),
– cleansing (or cleaning or scrubbing),
– transformation,
– loading.
• In a three-layer architecture, ETL processes actually feed the reconciled data layer
in to:
– A single ,
– Detailed ,
– Comprehensive ,
– Top-quality data source that in its turn feeds the data warehouse.

Decision support applications IBM ICE (Innovation Centre for Education)
IBM Power Systems
• Successfully supporting managerial decision making has become critically
dependent upon the
– Availability of integrated.
– High quality information organized .
– Presented to managers in a timely and easily understood manner.
• Data warehouses have emerged to meet this need.
– Surrounded by analytical tools and models.
– data warehouses have the potential to transform operational data into business intelligence.
• Content Management

Unit summary IBM ICE (Innovation Centre for Education)
IBM Power Systems
Having completed this unit, you should be able to
• Know what data warehouse is
• Describe the architecture of data warehouse.
• Explain about data staging and ETL.
• Understand the need of content management.

Chapter 1

More Related Content

What's hot (8)

Similar to Chapter 1 (20)

Recently uploaded (20)

Chapter 1