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BUSINESS DRIVEN TECHNOLOGY Chapter Seven: Storing Organizational Information - Databases LEARNING OUTCOMES 7.1 Define the fundamental concepts of the relational database model 7.2 Evaluate the advantages of the relational database model 7.3 Compare operational integrity constraints and business-critical integrity constraints LEARNING OUTCOMES 7.4 Describe the role and purpose of a database management system 7.5 List and describe the four components of a database management system 7.6 Describe the two primary methods for integrating information across multiple databases CHAPTER SEVEN OVERVIEW • Information is everywhere in an organization • Information is stored in databases – Database – maintains information about various types of objects (inventory), events (transactions), people (employees), and places (warehouses) CHAPTER SEVEN OVERVIEW RELATIONAL DATABASE FUNDAMENTALS • There are numerous database models including: – Hierarchical database – stores related information in terms of predefined categorical relationships in a “treelike” fashion – Network database – used by a network installation tool to allocate and track network resources – Relational database model – stores information in the form of logically related two-dimensional tables Coca-Cola Bottling Company of Egypt • Over 7,400 employees, owns and operate 11 bottling plants, 29 sales and distribution centers • Implemented an inventory-tracking database – Improve order accuracy by 27% – Decrease order response time by 66% – Increase sales by 20% • Traditionally, the company sent distribution trucks to each customer’s premises to take orders and deliver stock Coca-Cola Bottling Company of Egypt (2) • There were many problems associated with such process: – Numerous information entry errors, which caused orderfulfillment time to take an average of three days. • To remedy the situation, Coca-Cola decided – To create presales teams equipped with hand-held devices to visit customers and take orders electronically. On returning to the office, the teams synchronized orders with the company’s inventorytracking database. Entities, Entity Classes, and Attributes • Entity – a person, place, thing, transaction, or event about which information is stored – The rows in each table contain the entities – Figure 2.6 on page 63, CUSTOMER includes Dave’s Sub Shop and Pizza Palace entities • Entity class (table) – a collection of similar entities – Figure 2.6 on page 63 includes CUSTOMER, ORDER, ORDER LINE, DISTRIBUTOR, and PRODUCT entity classes Entities, Entity Classes, and Attributes • Attributes (fields, columns) – characteristics or properties of an entity class – The columns in each table contain the attributes – Figure 2.6 on page 63, attributes for CUSTOMER include Customer ID, Customer Name, Contact Name, and Phone Keys and Relationships • Primary keys and foreign keys identify the various entity classes (tables) in the database – Primary key – a field (or group of fields) that uniquely identifies a given entity in a table – Foreign key – a primary key of one table that appears an attribute in another table and acts to provide a logical relationship among the two tables Keys and Relationships Keys and Relationships • Potential relational database for Coca-Cola RELATIONAL DATABASE ADVANTAGES • Database advantages from a business perspective include – Increased flexibility – Increased scalability and performance – Reduced information redundancy – Increased information integrity (quality) – Increased information security Increased Flexibility • A well-designed database should: – Handle changes quickly and easily – Provide users with different views – A database has only one physical view • Physical view – deals with the physical storage of information on a storage device such as a hard disk – A database can have multiple logical views • Logical view – focuses on how users logically access information to meet particular business needs • e.g. one person could perform a query to determine which distributors delivered shipments to Pizza Palace last week, while another person could perform some sort of statistical analysis to determine the frequency at which Sprite and Diet Coke appear on the same order. Increased Scalability and Performance • A database must scale to meet increased demand, while maintaining acceptable performance levels – Scalability – refers to how well a system can adapt to increased demands – Performance – measures how quickly a system performs a certain process or transaction • Some organizations must be able to support hundreds or thousands of online users including employees, partners, customers and suppliers, who all want to access and share information. • Databases today scale to exceptional levels, allowing all types of users and programs to perform information-processing and information-searching tasks. Reduced Information Redundancy • Databases reduce information redundancy – Redundancy – the duplication of information or storing the same information in multiple places – Redundant information occurs because organizations frequently capture and store the same information in multiple locations. • Inconsistency is one of the primary problems with redundant information – Which makes it difficult to determine which values are the most current or most accurate – Not having correct information is confusing and frustrating for employees and disruptive to an organization. • Eliminating information redundancy saves space, makes performing information updates easier, and improves information quality. Increase Information Integrity (Quality) • Information integrity – a measure of the quality of information • Integrity constraints – rules that help ensure the quality of information – Operational integrity constraints – rules that enforce basic and fundamental information-based constraints e.g. not allow to create an order for nonexistent customer, provide a negative mark up percentage, order zero pounds of raw materials – Business-critical integrity constraints – rules that enforce business rules vital to an organization’s success and often require more insight and knowledge than operational integrity constraints e.g. a supplier might implement a constraint stating that no product returns are accepted after 15 days past delivery. Increased Information Security • Information is an organizational asset and must be protected • Databases offer several security features including: – Passwords – provide authentication of the user – Access levels – determine who has access to the different types of information – Access controls – Determine types of user access, such as read-only access • Various security features of databases can ensure that individuals have only certain types of access to certain type of information An example: CLEAR • Database can increase personal security as well as information security. Since 1995, the Chicago Police Department (CPD) has relied on a crimefighting system called Citizen and Law Enforcement Analysis and Reporting (CLEAR). • CLEAR electronically streamlines the way detectives enter and access critical information to help them solve crimes, analyze crime patterns, and ultimately promote security in a proactive manner. 650,000 new cases/500,00 new arrests An example: HOMOLOGATION TIMING • Ford’s European plant manufactures more than 5,000 vehicles a day and sells them in over 100 countries worldwide. • Every component of every model must conform to complex European standards – Passenger Safety, Pedestrian and Environmental • These standards govern each stage of manufacturing process from design to final production. • The company needs to obtain many thousands of different approvals each year to comply with the standards. • Overlooking just one means the company cannot sell the finished vehicle, which brings the production line to a standstill and could potentially cost Ford up to 1 million Euros per day. • So Homologation Timing System help Ford track and analyze these standards and then finally help Ford substantially reduce its compliance risk. DATABASE MANAGEMENT SYSTEMS • Database management systems (DBMS) – software through which users and application programs interact with a database DATABASE MANAGEMENT SYSTEMS • Four components of a DBMS Data Definition Component • Data definition component – helps create and maintain the data dictionary and the structure of the database • The data definition component includes the data dictionary – Data dictionary – a file that stores definitions of information types, identifies the primary and foreign keys, and maintains the relationships among the tables Data Definition Component • The data dictionary essentially defines the logical properties of the information that the database contains Data Manipulation Component • Data manipulation component – allows users to create, read, update, and delete information in a database • A DBMS contains several data manipulation tools: – Views – Allows users to see, change, sort, and query the database content – Report generators – users can define report formats along with the information they want to see – Query-by-example (QBE) – users can graphically design the answers to specific questions – Structured query language (SQL) – query language Data Manipulation Component • Sample report using Microsoft Access Report Generator Data Manipulation Component • Sample report using Microsoft Access Query-ByExample (QBE) tool Data Manipulation Component • Results from the query in Figure 2.11 Data Manipulation Component • SQL version of the QBE Query in Figure 2.11 Application Generation and Data Administration Components • Application generation component – includes tools for creating visually appealing and easy-to-use applications e.g. SCM application with menu to enter supplier, order, and order status • Data administration component – provides tools for managing the overall database environment by providing faculties for backup, recovery, security, and performance e.g. CPO direct the use of security component, implement policies and procedures concerning who has an access to different types of information • IT specialists primarily use these components INTEGRATING INFORMATION AMONG MULTIPLE DATABASES • Organizations typically maintain multiple systems, each with its own database • Integration – allows separate systems to communicate directly with each other • Integrations are expensive and difficult to build and maintain. • Most organizations build only forward integration e.g. sales through billing, implies that only a change in the initial system will result in changes in other systems. INTEGRATING INFORMATION AMONG MULTIPLE DATABASES • Forward integration – takes information entered into a given system and sends it automatically to all downstream systems and processes INTEGRATING INFORMATION AMONG MULTIPLE DATABASES • Backward integration – takes information entered into a given system and sends it automatically to all upstream systems and processes INTEGRATING INFORMATION AMONG MULTIPLE DATABASES • Building a central repository specifically for integrated information OPENING CASE STUDY QUESTIONS Searching for Revenue - Google 1. Identify the different types of entity classes that might be stored in Google’s indexing database 2. Explain why database technology is so important to Google’s business model 3. Explain the difference between logical and physical views and why logical views are important to Google’s employees CHAPTER SEVEN CASE Hotcourses Increases Revenues by 60 Percent • Hotcourses is one of the hottest new ebusinesses in London • Offers a comprehensive online educational marketplace • After two years of operation the company estimates revenues for 2003 between $100 and $500 million CHAPTER SEVEN CASE QUESTIONS 1. Identify the different types of entity classes and attributes potentially maintained in the Hotcourses database 2. Describe the two different ways that employees at Hotcourses might access the information in their databases 3. Create two questions that a manager at Hotcourses could turn into queries and run against a database to discover business intelligence