Business Driven Information Systems 2e CHAPTER 6 DATABASES AND DATA WAREHOUSES McGraw-Hill/Irwin ©2009 The McGraw-Hill Companies, All Rights Reserved SECTION 6.1 DATABASE FUNDAMENTALS McGraw-Hill/Irwin ©2009 The McGraw-Hill Companies, All Rights Reserved 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-todate 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 CocaCola 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 SECTION 6.2 DATA WAREHOUSE FUNDAMENTALS McGraw-Hill/Irwin ©2009 The McGraw-Hill Companies, All Rights Reserved 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