Managing Data Resources Chapter 6 Managing Data Resources

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources OBJECTIVES Describe basic file organization concepts and the problems of managing data resources in a traditional file environment Describe how a database management system organizes information, and compare the principal database models Apply important database design principles

Evaluate new database trends Management Information Systems Chapter 6 Managing Data Resources OBJECTIVES (Continued) Evaluate new database trends Identify the challenges and key management decisions posed by data resource management

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources VIRGIN MOBILE AUSTRALIA CASE Challenge: Fragmented and isolated corporate systems creating a single integrated view of customers and operations Solution: single integrated corporate data warehouse, using a single data model. Oracle 9i database provides near real-time access to customer activity, customer profitability, and customer reactions Illustrates the importance of managing data resources for achieving profitability

File Organization Terms and Concepts Management Information Systems Chapter 6 Managing Data Resources ORGANIZING DATA IN A TRADITIONAL FILE ENVIRONMENT File Organization Terms and Concepts Bit: Smallest unit of data; binary digit (0,1) Byte: Group of bits that represents a single character Field: Group of words or a complete number Record: Group of related fields File: Group of records of same type

File Organization Terms and Concepts (continued) Management Information Systems Chapter 6 Managing Data Resources ORGANIZING DATA IN A TRADITIONAL FILE ENVIRONMENT File Organization Terms and Concepts (continued) Database: Group of related files Entity: Person, place, thing, event about which information is maintained Attribute: Description of a particular entity Key field: Identifier field used to retrieve, update, sort a record

The Data Hierarchy Management Information Systems Chapter 6 Managing Data Resources ORGANIZING DATA IN A TRADITIONAL FILE ENVIRONMENT The Data Hierarchy

Entities and Attributes Management Information Systems Chapter 6 Managing Data Resources ORGANIZING DATA IN A TRADITIONAL FILE ENVIRONMENT Entities and Attributes

Data Redundancy and Inconsistency: Management Information Systems Chapter 6 Managing Data Resources ORGANIZING DATA IN A TRADITIONAL FILE ENVIRONMENT Problems with the Traditional File Environment Data Redundancy and Inconsistency: Data redundancy: The presence of duplicate data in multiple data files so that the same data are stored in more than one place or location Data inconsistency: The same attribute may have different values.

Program-Data Dependence: Management Information Systems Chapter 6 Managing Data Resources ORGANIZING DATA IN A TRADITIONAL FILE ENVIRONMENT Problems with the Traditional File Environment (continued) Program-Data Dependence: The coupling of data stored in files and the specific programs required to update and maintain those files such that changes in programs require changes to the data

Management Information Systems Chapter 6 Managing Data Resources ORGANIZING DATA IN A TRADITIONAL FILE ENVIRONMENT Problems with the Traditional File Environment (continued) Lack of Flexibility A traditional file system can deliver routine scheduled reports after extensive programming efforts, but it cannot deliver ad-hoc reports or respond to unanticipated information requirements in a timely fashion

Management Information Systems Chapter 6 Managing Data Resources ORGANIZING DATA IN A TRADITIONAL FILE ENVIRONMENT Problems with the Traditional File Environment (continued) Poor security Management may have no knowledge of who is accessing or making changes to the organization’s data Lack of data sharing and availability: Information cannot flow freely across different functional areas or different parts of the organization.

Traditional File Processing Management Information Systems Chapter 6 Managing Data Resources ORGANIZING DATA IN A TRADITIONAL FILE ENVIRONMENT Traditional File Processing

Database Management System (DBMS) Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Database a collection of data organized to serve many applications efficiently by centralizing data and controlling redundant data Database Management System (DBMS) Software that permits an organization to centralize data, manage them efficiently, and provide access to the stored data

Database Management System (continued) Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Database Management System (continued) Acts as interface between application programs and physical data files Separates logical and design views of data Solves many problems of the traditional data file approach

The Contemporary Database Environment Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT The Contemporary Database Environment

Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Components of a DBMS Data definition language: Specifies content and structure of database and defines each data element Data manipulation language: Used to process data in a database Data dictionary: Stores definitions of data elements and data characteristics

Sample Data Dictionary Report Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Sample Data Dictionary Report

Types of Databases Relational DBMS Hierarchical and Network DBMS Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Types of Databases Relational DBMS Hierarchical and Network DBMS Object-oriented DBMS

Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Relational DBMS Represents data as two-dimensional tables called relations Relates data across tables based on common data element Examples: DB2, Oracle, MS SQL Server

The Relational Data Model Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT The Relational Data Model

Three Basic Operations in a Relational DBMS Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Three Basic Operations in a Relational DBMS Select: Creates subset of rows that meet specific criteria Join: Combines relational tables to provide users with information Project: Enables users to create new tables containing only relevant information

The Three Basic Operations of a Relational DBMS Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT The Three Basic Operations of a Relational DBMS

Hierarchical and Network DBMS Hierarchical: Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Hierarchical and Network DBMS Hierarchical: Organizes data in a tree-like structure Supports one-to-many parent-child relationships Prevalent in large legacy systems Network: Depicts data logically as many-to-many relationships

A Hierarchical Database for a Human Resources System Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT A Hierarchical Database for a Human Resources System

The Network Data Model Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT The Network Data Model

Hierarchical and Network DBMS Disadvantages: Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Hierarchical and Network DBMS Disadvantages: Outdated, not used for new applications Less flexible compared to RDBMS Lack support for ad-hoc and English language-like queries

Object-oriented Database Management Systems (OODBMS): Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Object-oriented Database Management Systems (OODBMS): Stores data and procedures as objects that can be retrieved and shared automatically Provides capabilities of both object-oriented and relational DBMS Hybrid OODBMS: combine benefits of relational and object-oriented DBMS

Management Information Systems Chapter 6 Managing Data Resources THE DATABASE APPROACH TO DATA MANAGEMENT Designing Databases Conceptual design: Abstract model of database from a business perspective Physical design: Detailed description of business information needs Entity-relationship diagram: Methodology for documenting databases illustrating relationships between database entities Normalization: Process of creating small stable data structures from complex groups of data

An Unnormalized Relation for ORDER Management Information Systems Chapter 6 Managing Data Resources CREATING A DATABASE ENVIRONMENT An Unnormalized Relation for ORDER

Normalized Tables Created from ORDER Management Information Systems Chapter 6 Managing Data Resources CREATING A DATABASE ENVIRONMENT Normalized Tables Created from ORDER

An Entity-Relationship Diagram Management Information Systems Chapter 6 Managing Data Resources CREATING A DATABASE ENVIRONMENT An Entity-Relationship Diagram

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources CREATING A DATABASE ENVIRONMENT Distributed database: A database that is stored in more than one physical location Reduce the vulnerability of a single, massive central site Increase service and responsiveness to local users Can often run on smaller, less expensive computers Depend on high-quality telecommunications lines

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources CREATING A DATABASE ENVIRONMENT Distributed Databases (continued) Can be decentralized either by partitioning or by replicating Partitioned database: Parts of the database are stored in different physical locations Replicated database: Duplicate the entire database at all remote locations

Distributed Databases Management Information Systems Chapter 6 Managing Data Resources CREATING A DATABASE ENVIRONMENT Distributed Databases

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources CREATING A DATABASE ENVIRONMENT Ensuring Data Quality The quality of decision making in a firm is directly related to the quality of data in its databases. Data Quality Audit: Structured survey of the accuracy and level of completeness of the data in an information system Data Cleansing: Consists of activities for detecting and correcting data in a database or file that are incorrect, incomplete, improperly formatted, or redundant

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources DATABASE TRENDS Multidimensional Data Analysis Also called Online Analytical Processing (OLAP) Supports manipulation and analysis of large volumes of data from multiple dimensions/perspectives

Multidimensional Data Model Management Information Systems Chapter 6 Managing Data Resources DATABASE TRENDS Multidimensional Data Model

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources DATABASE TRENDS Data Warehouses and Data Mining Data Warehouse A massive database that stores current and historical data Data are standardized into a common data model Consolidated across entire enterprise for management analysis and decision making

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources DATABASE TRENDS Components of a Data Warehouse

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources DATABASE TRENDS Data Mart Subset of data warehouse Contains summarized or highly focused portion of data for a specified function or group of users Data Mining Tools for analyzing large pools of data Find hidden patterns and infer rules to predict trends

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources DATABASE TRENDS Benefits of Data Warehouses Improved information Easier access to information Ability to model and remodel the data

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources DATABASE TRENDS Databases and the Web The Web and Hypermedia Databases Organizes data as network of nodes Links nodes in pattern specified by user Supports text, graphic, sound, video, and executable programs

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources DATABASE TRENDS A Hypermedia Database

Databases and the Web (continued) Management Information Systems Chapter 6 Managing Data Resources DATABASE TRENDS Databases and the Web (continued) Linking Internal Databases to the Web Database server: Computer in a client/server environment runs a DBMS to process SQL statements and perform database management tasks. Application server: Software handling all application operations

Linking Internal Databases to the Web Management Information Systems Chapter 6 Managing Data Resources DATABASE TRENDS Linking Internal Databases to the Web

The ThomasNet.com Web database interface Management Information Systems Chapter 6 Managing Data Resources DATABASE TRENDS The ThomasNet.com Web database interface

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources MANAGEMENT OPPORTUNITIES, CHALLENGES, AND SOLUTIONS Opportunities Organizational performance can be improved by making better use of data Investments in data mining and customer relationship management technology

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources MANAGEMENT OPPORTUNITIES, CHALLENGES, AND SOLUTIONS Challenges Organizational obstacles to a database environment Need cooperation to develop corporate-wide data administration Cost/benefit considerations Bringing about significant change in the database environment of a firm can be very expensive and time consuming

Management Information Systems Managing Data Resources Chapter 6 Managing Data Resources MANAGEMENT OPPORTUNITIES, CHALLENGES, AND SOLUTIONS Solution Guidelines The critical elements for creating a database environment are: Data administration Data-planning and modeling methodology Database technology, management and users

Key Organizational Elements in the Database Environment Management Information Systems Chapter 6 Managing Data Resources MANAGEMENT OPPORTUNITIES, CHALLENGES, AND SOLUTIONS Key Organizational Elements in the Database Environment