Chapter 5 Data Resource Management McGraw-Hill/Irwin Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved. Learning Objectives Explain the value of implementing data resource management processes and technologies in an organization. Outline the advantages of a database management approach to managing the data resources of a business, compared with a file processing approach. Explain how database management software helps business professionals and supports the operations and management of a business. 5-2 Learning Objectives Provide examples to illustrate each of the following concepts: Major types of databases Data warehouses and data mining Logical data elements Fundamental database structures Database development 5-3 Section 1 Technical Foundations of Database Management 5-4 I. Database Management System Data resources must be structured and organized in some logical manner so they can be accessed, processed, retrieved, and managed easily 5-5 II. Fundamental Data Concepts Character – the most basic logical data element that can be observed, a single alpha or numeric or other symbol, represented by one byte Field – a grouping of related characters, as a last name or a salary, represents an attribute of some entity General Purpose Application Programs – perform common information processing jobs for end users 5-6 II. Fundamental Data Concepts Record – a grouping of attributes that describe an entity File – a group of related data records Database – a collection of logically related data elements 5-7 II. Fundamental Data Concepts 5-8 III. Database Structures (Models) Hierarchical Structure – treelike structure of oneto-many parent-child relationships (each child can have only one parent) Network Structure – similar to hierarchical but allows many-to-many relationships (a child record can have more than one parent) Relational Structure – the most widely used database model today; data is represented as a series of two-dimensional tables called Relations; each column is a named attribute of the entity, each row is an unnamed instance of that entity 5-9 III. Database Structures (Models) Relational Operations Select – create a subset that meets a criterion Join – temporarily combine two or more tables for comparison Project – create a subset of the columns in the temporary tables Multidimensional Structure – variation of the Relational model using multidimensional structures to organize and express relationships 5-10 III. Database Structures (Models) 5-11 III. Database Structures (Models) 5-12 III. Database Structures (Models) 5-13 III. Database Structures (Models) Object-Oriented Structure – combining the data of interest and the processes that act on that data into a structure called an object Encapsulation – allows complex data types Inheritance – allows replication of some/all of the characteristics of a parent object in the creation of a child object Evaluation of Database Structures – databases have grown more complex as needs have changed and grown in complexity 5-14 III. Database Structures (Models) 5-15 Database Pioneer Rethinks the Best Way to Organize Data How do databases currently focus on data to be stored? What is suggested as a better away to focus on data warehouses? What gains do these changes promise? 5-16 IV. Database Development Database Administrator (DBA) – controls development and administration of the database Data Definition Language (DDL) – used to specify the contents, relationships, and structure of the database Data Dictionary – directory containing the metadata 5-17 IV. Database Development Metadata – data about the data Data Planning and Database Design Data Modeling (Entity-Relationship Diagrams) – logical models of the data itself; this must be done before choosing the database model Schema – the physical/internal view of a system Subschema – the logical/external view of a system 5-18 IV. Database Development 5-19 IV. Database Development Entity Relationship Diagram 5-20 AAA Missouri: Data Quality Is an Important First Step What problem did AAA Missouri have? How does Melissa solve this problem? What other benefits does this software provide? What is the ultimate goal of using this software? What business benefit will that provide? 5-21 Hadoop: Ready for the Large-scale Databases of the Future What is the strength of Hadoop? What does Hadoop do differently from pervious databases? Why do we need something different today for handling data in databases? What does this tell you about the future od handling data? 5-22 Section 2 Managing Data Resources 5-23 I. Data Resource Management Data are an organizational resource that must be managed as any other resource 5-24 I. Data Resource Management Types of Databases Used by Organizations and End-Users 5-25 II. Types of Databases Operational Databases – store detailed data to support business processes and operations Distributed Databases – many organizations distribute their databases over multiple locations Replication – complex process of updating distributed data Duplication – simplified method of updating distributed data 5-26 II. Types of Databases External Databases – outside the firm, free or fee-based Hypermedia Databases – hyperlinked pages of multimedia 5-27 Coty: Using Real-Time Analytics to Track Demand What percentage of retails products are usually out of stock in the U.S.? What percentage of promotional items are usually out of stock in the U.S.? What effect does this have on business? How does Coty deal with these issues? 5-28 III. Data Warehouses and Data Mining Data Warehouse – stores data extracted from other databases Data Mart – subset of a data warehouse focusing on a single topic, customer, product, etc. Data Mining – analyzing a data warehouse to reveal hidden patterns and trends 5-29 III. Data Warehouses and Data Mining Components of a Data Warehouse System 5-30 III. Data Warehouses and Data Mining A Data Warehouse and its Data Mart Subsets 5-31 III. Data Warehouses and Data Mining Data Mining Extracts Business Knowledge from a Data Warehouse 5-32 Better Analytics Means Better Care According to this case, what is the state of healthcare and BI? In what ways did the system improve patients’ health? How does SETMA view the cost and benefits of the system? 5-33 IV. Traditional File Processing Data was stored in independent files without regard to other needs for that data Problems of File Processing – databases seek to solve these problems 1. Data Redundancy – the same data is kept in more than one location; databases seek to Control (NOT reduce!) Redundancy; this led to Data Inconsistency – same data in multiple locations but the Values were Different 5-34 IV. Traditional File Processing Problems of File Processing – databases seek to solve these problems 2. Lack of data Integration – data not easily available for ad hoc requests 3. Data Dependence – data and programs were “tightly coupled”, changing one meant having to change the other 4. Lack of Data Integrity (Standardization) – data was defined differently by different end users or applications 5-35 Online Dating: The Technology Behind Finding Love Are all dating sites the same? For users, what makes the difference between different dating sites? What is the biggest challenge for eHarmony? When is the demand for eHarmony’s services greatest? Why might this be? What does this mean from a business perspective? 5-36 V. Database Management Approach Consolidate the data from separate files into databases accessible by multiple application programs Database Management System (DBMS) – a collection of programs to create, maintain, and use (retrieve) data in a database Database Maintenance – organizational databases need to be updated continually Application Development – facilitated by the Data Manipulation Language (DML) provided by the DBMS 5-37 V. Database Management Approach Database Interrogation – query (“ask”) the database for information Query Language – allows ad hoc requests of the database SQL Queries (Structured Query Language) – standard query language found in many databases Boolean Logic – 3 logical operators: AND, OR, and NOT Graphical and Natural Queries – easier methods of structuring SQL statements 5-38