McGraw-Hill/Irwin ©2009 The McGraw-Hill Companies, All Rights Reserved

CHAPTER 6

DATABASES AND DATA WAREHOUSES

CHAPTER 6

DATABASES AND DATA WAREHOUSES

Business Driven Information Systems 2eBusiness Driven Information Systems 2eBusiness Driven Information Systems 2eBusiness Driven Information Systems 2e

McGraw-Hill/Irwin ©2009 The McGraw-Hill Companies, All Rights Reserved

SECTION 6.1SECTION 6.1

DATABASE FUNDAMENTALS

DATABASE FUNDAMENTALS

6-3

Database Fundamentals

• Database – maintains information about various types of objects (inventory), events (transactions), people (employees), and places (warehouses)

6-4

The Value of Transactional and Analytical Information

6-5

The Value of Timely Information

• Timeliness is an aspect of information that depends on the situation– Real-time information – immediate, up-to-

date information– Real-time system – provides real-time

information in response to query requests

6-6

The Value of Quality Information

• Characteristics of high-quality information include:– Accuracy– Completeness– Consistency– Uniqueness – Timeliness

6-7

Understanding the Costs of Poor Information

• Potential business effects from low quality information:– Inability to accurately track customers– Difficulty identifying valuable customers– Inability to identify selling opportunities– Marketing to nonexistent customers– Difficulty tracking revenue– Inability to build strong customer relationships

6-8

Relational Database Fundamentals

• Relational database model – stores information in the form of logically related two-dimensional tables

• Other DB Models– Hierarchical database model– Network database model – Flat– Object oriented

6-9

Entities and Attributes

• Entity – a person, place, thing, transaction, or event about which information is stored

• Attribute (field, column) – characteristics or properties of an entity class

6-10

Hierarchy of Data

6-11

Keys and Relationships

• Primary keys and foreign keys identify the various entities in the database– Primary key – a field (or group of fields) that

uniquely identifies a given record in a table– Foreign key – a primary key of one table that

appears as an attribute in another table which provide a logical relationship among the two tables

6-12

• Potential relational database for Coca-Cola

6-13

Database Concerns

• Scalability – refers to how well a system can adapt to increased demands

• Performance – measures how quickly a system performs a certain process or transaction

6-14

Database Advantages

• Databases reduce information redundancy– Redundancy – the duplication of information

or storing the same information in multiple places

• Inconsistency is one of the primary problems with redundant information

6-15

Increase Information Integrity (Quality)

• Information integrity – measures the quality of information

• Integrity constraint – rules that help ensure the quality of information– Relational integrity constraint– Business-critical integrity constraint

6-16

Database Management Systems

• Database management systems (DBMS) – software through which users and application programs interact with a database

6-17

Integrating Information among Multiple Databases

• Building a central repository specifically for integrated information

McGraw-Hill/Irwin ©2009 The McGraw-Hill Companies, All Rights Reserved

SECTION 6.2SECTION 6.2

DATA WAREHOUSE FUNDAMENTALS

DATA WAREHOUSE FUNDAMENTALS

6-19

DATA WAREHOUSE FUNDAMENTALS

• Data warehouse – a logical collection of information – gathered from many different operational databases – that supports business analysis activities and decision-making tasks

• Data mart – contains a subset of data warehouse information

6-20

DATA WAREHOUSE FUNDAMENTALS

6-21

Information Cleansing or Scrubbing

• Standardizing Customer name from Operational Systems

6-22

Information Cleansing or Scrubbing

• Accurate and complete information

6-23

Data Mining and Business Intelligence

• Data mining – the process of analyzing data to extract information not offered by the raw data alone

• To perform data mining users need data-mining tools

• Data-mining tools helps users uncover BI