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3 Database Resource Management I. CHAPTER OVERVIEW Foundation Concepts: Foundations of Information in Business presents an overview of the five basic areas of information systems knowledge needed by business professionals, including the conceptual system components and major types of information systems. Data Resource Management – Data resource management is a managerial activity that applies information systems technology and management tools to the task of managing an organization’s data resources. It includes the database administration function that focuses on developing and maintaining standards and controls for an organization’s databases. Data administration, however, focuses on the planning and control of data to support business functions and strategic organizational objectives. This includes a data planning effort that focuses on developing an overall data architecture for a firm’s data resources. Database Management - The database management approach affects the storage and processing of data. The data needed by different applications are consolidated and integrated into several common databases, instead of being stored in many independent data files. Also, the database management approach emphasizes updating and maintaining common databases, having users’ application programs share the data in the database, and providing a reporting and an inquiry/response capability so end users can easily receive reports and quick responses to requests for information. Database Software - Database management systems are software packages that simplify the criterion, use, and maintenance of databases. They provide software tools so end users, programmers, and database administrators can create and modify databases, interrogate a database, generate reports, do application development, and perform database maintenance. Types of Databases - Several types of databases are used by business organizations, including operational, distributed, and external databases. Data warehouses are a central source of data from other databases that have been cleaned, transformed and cataloged for business analysis and decision support applications. That includes data mining, which attempts to find hidden patterns and trends in the warehouse data. Hypermedia databases on the World Wide Web and corporate intranets and extranets store hyperlinked multimedia pages at a website. Web server software can manage such databases for quick access and maintenance of the Web database. Database Development - The development of databases can be easily accomplished using microcomputer database management packages for small end user applications. However, the development of large corporate databases requires a top-down data planning effort. This may involve developing enterprise and entity relationship models, subject area databases, and data models that reflect the logical data elements and relationships needed to support the operation and management of the basic business processes of the organization. Data Access - Data must be organized in some logical manner on physical storage devices so that they can be efficiently processed. For this reason, data are commonly organized into logical data elements such as characters, fields, records, files, and databases. Database and object-oriented models, are used to organize the relationships among the data records stored in databases. Databases and files can be organized in either a sequential or direct manner and can be accessed and maintained by either sequential access or direct access processing methods. II: LEARNING OBJECTIVES Learning Objective Explain the importance of implementing data resource management processes and technologies in an organization. Outline the advantages of the database management approach to managing the data resources of a business. 37 Explain how database management software helps business professionals and supports the operations and management of a business. Provide examples to illustrate each of the following concepts: a. Major types of databases. b. Data warehouses and data mining. c. Logical data elements. d. Fundamental database structures e. Database access methods. f. Database development. III. TEACHING SUGGESTIONS The purpose of this chapter is to provide students with an understanding of basic concepts and managerial implications of data resource management. Figure 3.1 may serve to review the logical data elements in an information system. It outlines the fundamental concepts of how data is organized in information systems. Figure 3.3 can be used to explain the major types of databases used by organizations and end users (operational, analytical, data warehouse, distributed, end user, and external databases). Figure 3.5 shows how you might use a web browser on your client PC to connect with a web network server. Figure 3.6 illustrates the components of a complete data warehouse system. Stress to students how data from various operational and external databases are captured, cleaned, and transformed into data that can be better used for analysis. Figure 3.9 can be used to discuss the four major uses of a DBMS package (database development, database interrogation, database maintenance, and application development). The three major data resource management activities (data administration, data planning, and database administration) can be discussed using Figure 13.14. Section II of the chapter provides some technical background for database management. Figure 3.15 can be used to explain and give examples of three fundamental database structures (hierarchical, network, and relational). Figure 3.16 is an example of a multidimensional database structure that shows that each dimension can represent a different category, such as product type, region, sales channel, and time. Figure 3.21 explains how database development involves data planning and database design activities. Data models that support business processes are used to develop databases and application programs that meet the information needs of end users in organizations. If feasible, a data administrator may be invited to discuss issues in data resource management with the class. IV. LECTURE NOTES Section I: Managing Data Resources DATA RESOURCE MANAGEMENT Data is a vital organizational resource, which needs to be managed like other important business assets. Most organizations could not survive or succeed without quality data about their internal operations and external environment. Managers need to practice data resource management - a managerial activity that applies information systems technology like database management and other management tools to the task of managing an organization's data resources to meet the information needs of business users. Analyzing IBM versus Oracles We can learn a lot from this case about the major choices companies face in selecting database and applications software. Take a few minutes to this case, and we will discuss it (See Analyzing IBM versus Oracle in Section IX). FOUNDATION DATA CONCEPTS - [Figure 3.1] 38 A hierarchy of several levels of data has been devised that differentiates between different groupings, or elements, of data. Data are logically organized into: Character - A character is the most basic logical data element. It consists of a single alphabetic, numeric, or other symbol. Field - A field consists of a grouping of characters. A data field represents an attribute (a characteristic or quality) of some entity (object, person, place, or event). Record - Related fields of data are grouped to form a record. Thus, a record represents a collection of attributes that describe an entity. Fixed-length records contain a fixed number of fixed-length data fields. Variable-length records contain a variable number of fields and field lengths. File - A group of related records is known as a data file, or table. Files are frequently classified by the application for which they are primarily used, such as a payroll file or an inventory file, or the type of data they contain, such as a document file or a graphical image file. Files are also classified by their permanence, for example, a master file versus a transaction file. A transaction file would contain records of all transactions occurring during a period, whereas a master file contains all the permanent records. A history file is an obsolete transaction or master file retained for backup purposes or for long-term historical storage called archival storage. Database - A database is an integrated collection of logically related records or objects. A database consolidates records previously stored in separate files into a common pool of data records that provides data for many applications. The data stored in a database is independent of the application programs using it and of the type of secondary storage devices on which it is stored. TYPES OF DATABASES - [Figure 3.3] Continuing developments in information technology and its business applications have resulted in the evolution of several major types of databases. Several major conceptual categories of databases that may be found in computer-using organizations include: Operational Databases - These databases store detailed data needed to support the operations of the entire organization. They are also called subject area databases (SADB), transaction databases, and production databases. Examples are customer databases, personnel databases, inventory databases, and other databases containing data generated by business operations. Distributed Databases - Many organizations replicate and distribute copies or parts of databases to network servers at a variety of sites. These distributed databases can reside on network servers on the World Wide Web, on corporate Intranets or extranets, or on other company networks. Distributed databases may be copies of operational or analytical databases, hypermedia or discussion databases, or any other type of database. Replication and distribution of databases is done to improve database performance and security. External Databases - Access to external, privately owned online databases or data banks is available for a fee to end users and organizations from commercial online services, and with or without charge from many sources on the Internet, especially the Web. Hypermedia Databases on the Web: [Figure 3.5] - The rapid growth of web sites on the Internet and corporate Intranets and extranets has dramatically increased the use of databases of hypertext and hypermedia documents. A web site stores such information in a hypermedia database consisting of a home page and other hyperlinked pages of multimedia or mixed media (text, sound, etc.). DATA WAREHOUSES AND DATA MINING - [Figure 3.6] Data Warehouses - A data warehouse stores data from current and previous years that has been extracted from the various operational and management databases of an organization. It becomes a central source of data, which has been screened, edited, standardized, and integrated so it can be used by managers and other end user professionals throughout an organization. Data warehouses may be subdivided into data marts, which hold specific subsets of data from the warehouse. Data Mining - A major use of data warehouse databases is data mining. In data mining, the data in a data warehouse are processed to identify key factors and trends in historical patterns of business activity that can be used to help managers make decisions about strategic changes in business operations to gain competitive 39 advantages in the marketplace. THE DATABASE MANAGEMENT APPROACH The development of databases and database management software is the foundation of modern methods of managing organizational data. Database Management Approach - Is a method whereby data records and objects are consolidated into databases that can be accessed by many different application programs. Database Management System - (DBMS) serves as a software interface between users and databases. Thus, database management involves the use of database management software to control how databases are created, interrogated, and maintained to provide information needed by end users and their organizations. The database management approach involves three basic activities: Updating and maintaining common databases to reflect new business transactions and other events requiring changes to an organization’s records. Providing information needed for each end user’s application by using application programs that share the data in common databases. Providing an inquiry/response and reporting capability through a DBMS package so that end users can easily interrogate databases, generate reports, and receive quick responses to their ad hoc requests for information. Database Management Software: [Figure 3.9] A database management system (DBMS) is a set of computer programs that controls the creation, maintenance, and use of the databases of an organization and its end users. The four major uses of a DBMS include: Database Development Database Interrogation Database Maintenance Application Development Database Interrogation: The database interrogation capability is a major benefit of a database management system. End users can use a DBMS by asking for information from a database using a query language or a report generator. Features of a query language: - Users receive an immediate response in the form of video displays or printed reports. - No difficult program is required. - Users can obtain immediate responses to ad hoc data requests. Features of a report generator: - Users receive an immediate response in the form of video displays or printed reports. - No difficult program is required. - Users can specify a report format for information they want presented as a report. SQL, or Structured Query Language, is a query language found in many database management packages. It is used to obtaining immediate responses to ad hoc inquiries. Basic Form of an SQL query is: SELECT........... FROM.............WHERE SELECT:.....….. list the data fields you want retrieved FROM:........ list the fields or tables from which the data must be retrieved WHERE...... specify conditions that limit the search to only those data records in which you are interested 40 QBE, or Query by Example, is another form of query language found in some database management packages. The QBE method displays boxes for each of the data fields in one or more files. The end user simply “points-and-clicks” to indicate which information they want. Graphical and Natural Queries - Most end user database management packages offer GUI (graphical user interface) point-and-click methods to query a database. These methods are easy to use and are translated by the software into SQL commands. Other packages are available that use natural language query statements similar to conversational English. Database Maintenance and Transaction Processing: Managers need accurate information in order to make effective decisions. The more accurate, relevant, and timely the information, the better-informed management will be when making decisions. Thus, the databases of an organization need to be updated continually to reflect new business transactions and other events. Transaction processing programs and other end user application packages with the support of the DBMS accomplish this database maintenance process. Application Development: DBMS packages play a major role in application development. Application development is made easier by data manipulation language (DML) statements, which can be included in application programs to let the DBMS perform the necessary data handling activities. Programmers can also use the internal programming language provided by many DBMS packages or a built-in application generator to develop complex application programs. IMPLEMENTING DATA RESOURCE MANAGEMENT - [Figure 3.14] Managerial end users should view data as an important resource that they must learn to manage properly to ensure the success and survival of their organizations. Database management is an important application of information systems technology to the management of a firm’s data resources. Data resource management includes: Database Administration: - Is an important data resource management function responsible for the proper use of database management technology. Database administration has more operational and technical responsibilities than other data resource management functions. This includes responsibility for: - Developing and maintaining the organization’s data dictionary - Designing and monitoring the performance of databases - Enforcing standards for use and security. Data Planning: - Data planning is a corporate planning and analysis function that focuses on data resource management. It includes the responsibility for: - Developing an overall data architecture for the firm’s data resources that ties in with the firm’s strategic mission and plans, and the objectives and processes of its business units. - Data planning is a major component of an organization’s strategic planning process. It is done by organizations that have made a formal commitment to long-range planning for the strategic use and management of its data resources. Data Administration: - Is another data resource management function. It involves the: - Establishment and enforcement of policies and procedures for managing data as a strategic corporate resource. - Collection, storage, and dissemination of all types of data are administrated in such a way that data become a standardized resource available to all end users in the organization. - The planning and control of data in support of an organization’s business functions and strategic business objectives. - Establishment of a data planning activity for the organization. - Developing policies and set standards for corporate database design, processing, and security arrangements, and to select database management and data dictionary software. Challenges of Data Resource Management: The database resource management approach provides business managers and professionals with several important benefits such as: Reduce the duplication of data 41 Integrate data so that multiple programs and users can access them. Programs are not dependent on the format of the data and the type of secondary storage hardware being used. Users are provided with an inquiry/response and reporting capability that allows them to easily obtain information they need without having to write computer programs. Computer programming is simplified, because programs are not dependent on either the logical format of the data or their physical storage location. Integrity and security of the data stored in databases can be increased, since database management system software, a data dictionary, and a database administrator function control access to data and modification of the database. The limitations of database management arise from: Its increased technological complexity. Development of a large database and installing a DBMS can be difficult and expensive. More hardware capability is required, since storage requirements for the organization's data, overhead control data, and the DBMS programs are greater. Longer processing times may result from high-volume transaction processing applications since an extra layer of software (the DBMS) exists between application programs and the operating system. If an organization relies on centralized databases, their vulnerability to errors, fraud, and failures are increased. If an organization relies on distributed databases problems of inconsistency of data can arise. Section II: Technical Foundations of Database Management DATABASE MANAGEMENT In all information systems, data resources must be organized and structured in some logical manner so that they can be accessed easily, processed efficiently, retrieved quickly, and managed effectively. Data structures and access methods ranging from simple to complex have been devised to effectively organize and access data stored by information systems. Anaylzing Experian Automotive We can learn a lot about storage management software, functions, and strategies that are an important part of data resource management from this case. Take a few minutes to read it, and we will discuss it (See Experian Automotive in Section IX). DATABASE STRUCTURES - [Figure 3.15] The relationships among the many individual records in databases are based on one of several logical data structures or models. DBMS are designed to provide end users with quick, easy access to information stored in databases. Five fundamental database structures are: Hierarchical Structure: Early mainframe DBMS packages used the hierarchical structure, in which: - Relationships between records form a hierarchy or treelike structure. - Records are dependent and arranged in multilevel structures, consisting of one root record and any number of subordinate levels. - Relationships among the records are one-to-many, since each data element is related only to one element above it. - Data element or record at the highest level of the hierarchy is called the root element. Moving progressively downward from the root and along the branches of the tree until the desired record is located can access any data element. Network Structure: The network structure: 42 - Can represent more complex logical relationships, and is still used by many mainframe DBMS packages. - Allows many-to-many relationships among records. That is, the network model can access a data element by following one of several paths, because any data element or record can be related to any number of other data elements. Relational Structure: The relational structure: - Most popular of the three database structures. - Used by most microcomputer DBMS packages, as well as many minicomputer and mainframe systems. - Data elements within the database are stored in the form of simple tables. Tables are related if they contain common fields. - DBMS packages based on the relational model can link data elements from various tables to provide information to users. Multidimensional Structure: [Figure 3.16] The multidimensional database model: - Is a variation of the relational model that uses multidimensional structures to store data and relationships between data. - A major benefit of multidimensional databases is that they are a compact and easy-to- understand way to visualize and manipulate data elements that have many interrelationships. - Multidimensional databases have become the most popular database structure for the analytical databases that support online analytical processing (OLAP) applications. Object-Oriented Structure The object-oriented structure: - Is considered to be one of the key technologies of a new generation of multimedia web-based applications. - In an object-oriented structure, an object consists of data values describing the attributes of an entity plus the operations that can be performed upon the data. This encapsulation capability allows the object-oriented model to better handle more complex types of data (graphics, voice, text) than other database structures. - Supports inheritance, that is, new objects can be automatically created by replicating some or all of the characteristics of one or more parent objects. -Object capabilities and inheritance have made object-oriented database management systems (OODBMS) popular in computer-aided design (CAD) applications. Designers can develop product designs, store them as objects in an object-oriented database, and replicate and modify them to create new product designs. Multimedia web-based applications for the Internet and corporate Intranets and extranets have become a major application area for object technology. Object Technology and the Web Object-oriented database software is finding increased use in managing the hypermedia databases and Java applets on the World Wide Web and corporate Intranets and extranets. Industry proponents predict that object-oriented database management systems (OODBMS) will become the key software component that manages the hyperlinked multimedia pages and other types of data that support corporate web sites. Evaluation of Database Structures: MODEL Hierarchical Data Structure ADVANTAGES DISADVANTAGES Ease with which data can be stored and retrieved in structured, routine types of transactions. Hierarchical one-to-many relationships must be specified in advance, and are not flexible. Ease with which data can be extracted for reporting purposes. Cannot easily handle ad hoc requests for information. 43 Structured and routine types of transaction processing are fast and efficient. Modifying a hierarchical database structure is complex. Great deal of redundancy. Requires knowledge of a programming language. Network Structure More flexible that the hierarchical model. Network many-to-many relationships must be specified in advance. Ability to provide sophisticated logical relationships among the records. User is limited to retrieving data that can be accessed using the established links between records. Cannot easily handle ad hoc requests for information. Requires knowledge of a programming language. Multidimensional Structure Compact and easy to understand way to visualize and manipulate data elements that has many interrelationships. Not currently developed for broad business application use. Supports OLAP applications in which fast answers to complex business queries are required. Relational Structure Flexible in that it can handle ad hoc information requests. Cannot process large amounts of business transactions as quickly and efficiently as the hierarchical and network models. Easy for programmers to work with. End users can use this model with little effort or training. Easier to maintain than the hierarchical and network models. Object-Oriented Structure Handles complex types of data (graphics, pictures, voice, and text) better than other structures. Not currently developed for broad business use. Relatively easy to use. Key technology being used in multimedia web-based applications for the Internet and corporate intranets and extranets. Supports inheritance - new objects can be automatically created by replicating some or all of the characteristics of one or more parent objects. 44 ACCESSING DATABASES Databases and data files are stored on various types of storage media and are organized in a variety of ways to make it easier to access the data records they contain. In database maintenance, records or objects have to be continually added, deleted, or updated to reflect business transactions, and they also need to be accessed so information can be produced in response to end user requests. Key Fields Records usually contain one or more identification fields, or keys that identify the record, so that it can be located. Other methods also identify and link data records stored in several different database files. Hierarchical and network databases may use pointer fields. These are fields within a record that indicate (point to) the location of another record that is related to it in the same file, or in another file. Hierarchical and network database management systems use this method to link records so they can retrieve information from several different database files. Relational database management packages use primary keys to link records. Each table (file) in a relational database must contain a primary key. This field uniquely identifies each record in a file and must also be found in other related files. Sequential Access: One of the basic ways to access data is sequential access. This method uses a sequential organization, in which records are physically stored in a specified order according to a key field in each record. Advantages of sequential access: It is fast and efficient when dealing with large volumes of data that need to be processed periodically. Disadvantages of sequential access: Requires that all new transactions be sorted into the proper sequence for sequential access processing. Locating, storing, modifying, deleting or adding records in the file requires rearranging the file. Too slow to handle applications requiring immediate updating or responses. Direct Access: When using direct access methods, records do not have to be arranged in any particular sequence on storage media. Characteristics of the direct access method: Computers must keep track of the storage location of each record using a variety of direct organization methods so that data can be retrieved when needed. New transactions’ data do not have to be sorted. Processing that requires immediate responses or updating is easily handled. Three common ways to directly access records in the direct organization method include: Key Transformation: - This method performs an arithmetic computation on a key field or record and uses the number that results from that calculation as an address to store and access that record. Index: - This method uses an index of record keys and related storage addresses. A new data record is stored at the next available location, and its key and address are placed in an index. The computer uses this index, whenever it must access a record. Indexed Sequential Access Method (ISAM): - In this method records are physically stored in sequential order on a magnetic disk or other direct access storage device based on the key field of each record. Each file contains an index that references one or more key fields of each data record to its storage location address. DATABASE DEVELOPMENT 45 Developing small personal databases is relatively easy using microcomputer DBMS packages. However, developing a large database can be a complex task. In many companies, developing and managing corporate databases is the primary responsibility of the database administrator and database design analysts. They work with end users and systems analysts to determine: What data definitions should be included in the database What structure or relationships should exist among the data elements. Data Planning and Database Design: [Figure 3.21] Database development must start with a top-down data planning process. Database administrators work with corporate and end user management according to the following steps: Develop an enterprise model to define the basic business processes of the enterprise. Define the information needs of end users in a business process. Identify the key data elements that are needed to perform their specific business activities. Develop entity relationship diagrams (ERDs) that model the relationships among the many entities involved in the business process. The user views become the basis for the data modelling steps where the relationships between data elements are identified. Each data model defines the logical relationships among the data elements needed to support a basic business process. These data models then serve as logical frameworks (schemas and subschemas) on which to base the physical design of databases and the development of application programs to support the business processes of the organization. Data Models - Represent a logical view of the data and relationships of the data. Schema - Is an overall logical view of the relationships between data in a database. Subschema - Is a logical view of data relationships needed to support specific end user application programs that will access that database. Physical or Internal View - Looks at how data is physically arranged, stored, and accessed on the magnetic disks and other secondary storage devices of a computer system. V. KEY TERMS AND CONCEPTS - DEFINED Data Dictionary: A software module and database containing descriptions and definitions concerning the structure, data elements, interrelationships, and other characteristics of an organization’s databases. Data Mining: A process where data in a data warehouse is identified to discover key business trends and factors. Data Modeling: A process where the relationships between data elements are identified and defined to develop data models. Data Planning: A planning and analysis function focusing on data resource management which includes the responsibility of developing an overall information policy and data architecture for a company’s data resources. Data Resource Management: A managerial activity that applies information systems technology and management tools to the task of managing an organization’s data resources. Its three major components are database administration, data administration, and data planning. Database Access - Direct: A method of storage where each storage position has a unique address and can be individually accessed. 46 Database Access - Sequential: A method of storing and retrieving data where records are organized in sequential order by some key field. Database Administration: A data resource management function which includes responsibility for developing and maintaining the organization’s data dictionary, designing and monitoring the performance of databases, and enforcing standards for database use and security. Database Administrator: A specialist responsible for maintaining standards for the development, maintenance, and security of an organization’s databases. Database Management Approach: An approach to the storage and processing of data in which independent files are consolidated into a common pool or database of records available to different application programs and end users for processing and data retrieval. Database Management System (DBMS): A set of computer programs that controls the creation, maintenance, and utilization of the databases of an organization. Database Structure - Hierarchical: A logical data structure in which the relationships between records form a hierarchy or tree structure. The relationships among records are one-to-many, since each data element is related only to one element above it. Database Structure - Multidimensional: A multidimensional database model uses multidimensional structures to store data and relationships between data. Database Structure - Network: A logical database structure, which allows many-to-many relationships among data records. Database Structure - Object-Oriented: A logical database structure, which uses objects as data elements, i.e. elements that include both data and the methods or processes that act on the data. Database Structure - Relational: A logical data structure in which all data elements within the database are viewed as being stored in the form of simple tables. DBMS packages based on the relational model can link data elements from various tables as long as the tables share common data elements. DBMS uses: Includes application development, database development, database interrogation, and database maintenance. DBMS uses - Application Development: Database management packages allow end users to develop personalized applications to enhance work activity. DBMS uses - Database Development: Database management packages allow end users to develop databases that they need. DBMS uses - Database Interrogation: End users can obtain information from a database using a query language or a report generator. DBMS uses - Database Maintenance: The databases of an organization need to be updated continually to reflect new business transactions and other events. Key Field: A field within a data record that is used to identify it or control its use. 47 Logical Data Elements: Data elements that are independent of the physical data media on which they are recorded. Logical Data Elements - Character: The most basic logical data element, which consists of a single alphabetic, numeric, or other symbol. Logical Data Elements - Field: A data element that consists of a grouping of characters that describe a particular attribute of an entity. Logical Data Elements - Record: A collection of related data fields treated as a unit. Logical Data Elements- File: A collection of related data records treated as a unit. Sometimes called a data set. Logical Data Elements - Database: A collection of logically related records or files. A database consolidates many records previously stored in separate files so that a common pool of data records serves many applications. Metadata: Data about data; data describing the structure, data elements, interrelationships, and other characteristics of a database. Query Language: A high-level human-like language provided by a database management system that enables users to easily extract data and information from a database. Report Generator: A feature of database management system packages, which allows an end user to quickly specify a report format for the display of information, retrieved from a database. Types of Databases - Data Warehouse: A central source of data that has been extracted from various organizational databases and standardized and integrated for use throughout an organization. Types of Databases - Distributed: The concept of distributing databases or portions of a database at remote sites where the data is more frequently referenced. Sharing of data is made possible through a network that interconnects the distributed databases. Types of Databases - External: Commercially operated databases that provide information for a fee and that can be accessed through wide area networks. Types of Databases - Hypermedia: A web site stores information in a hypermedia database consisting of a home page and other hyperlinked pages of multimedia or mixed media (text, graphics and photographic images, video clips, audio segments, and so on). Types of Databases - Operational: Databases that support the major business operations of an entire organization. Also called subject area databases, transaction databases, and production databases. VI. REVIEW QUIZ - Match one of the key terms and concepts 48 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 (9) Database management approach (12) DBMS uses (7) Database administrator (16) Query language (1) Data dictionary (17) Report generator (10) Database management system (18b) Distributed (11d) Object-oriented (18d) Hypermedia (5) Data resource management (6) Database access (2) Data mining (4) Data planning (3) Data modelling (14b) Field (14c) Record (14d) File (14e) Database (13) Key field (11a) Hierarchical (11e) Relational (11b) Multidimensional (6a) Direct (6b) Sequential 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 (18e) Operational (18a) Data warehouse (18c) External VII. ANSWERS TO DISCUSSION QUESTIONS 1. How should an e-business enterprise store, access, and distribute data and information about their internal operations and external environments? Students’ responses may vary. However, there is a growing trend towards distributed databases residing on network servers on the World Wide Web, on corporate intranets or extranets, and on other company networks. 2. What roles do database management, data administration, and data planning play in managing data as a business resource? Data administration’s responsibility is to ensure that data become a standardized resource, available to all end users in the organization that needs these data. It involves the establishment and enforcement of policies and procedures for managing the corporate data. Database management’s responsibility is to ensure that databases are created, used, and maintained in accordance with the established policies and procedures. Data planning’s responsibility is to develop an overall information policy and data architecture for a company’s data resources. 3. What are the advantages of the database management approach to organizing, accessing, and managing an organization’s data resources? Give examples to illustrate your answer. The database management approach provides managerial end users with several important benefits such as: Reduce the duplication of data Integrate data so that multiple programs and users can access them. Programs are not dependent on the format of the data and the type of secondary storage hardware being used. Users are provided with an inquiry/response and reporting capability that allows them to easily obtain information they need without having to write computer programs. 49 4. Computer programming is simplified, because programs are not dependent on either the logical format of the data or their physical storage location. Integrity and security of the data stored in databases can be increased, since access to data and modification of the database are controlled by database management system software, a data dictionary, and a database administrator function. Refer to the Real World Case on IBM versus Oracle in the chapter. The case states that “database software has become more of a commodity.” Do you agree? Why or why not? Certainly, students’ will realize that in today’s information society that database software is not considered a luxury – it is one of the most basic commodities within a business. Organizations are aggressively pursuing and collecting valuable information that is captured, stored, and analyzed in order to gain competitive advantages. No company today can survive without much sought after commodity. 5. What is the role of a database management system in an e-business information system? A database management system is a set of computer programs that controls the creation, maintenance, and use of the databases of an organization. Major uses are database development, database interrogation, database maintenance, and development of application programs. 6. Databases of information about a firm’s internal operations were formerly the only databases that were considered to be important to a business. What other kinds of databases are important for a business today? Commercial, external databases provide external information to businesses, such as current economic statistics, or abstracts of professional periodicals. Without these external database services, it would take an enormous effort to obtain the same type of information, by having employees collect relevant data from multiple sources and process them. 7. Refer to the Real World Case on Canadian Blood Services in the chapter. What legitimate privacy concerns and safeguard suggestions might be raised about the CBS database and its use? The numerous points of entry to the CBS database mean that private information on donors is accessible from any number of computers by any number of users. Canadian Blood Services will need to ensure that widening access to information does not expose data unduly. 8. What are the benefits and limitations of the relational database model for business applications today? Benefits of the relational structure: Most popular of the three database structures. Used by most microcomputer DBMS packages, as well as many minicomputer and mainframe systems. Data elements within the database are stored in the form of simple tables. Tables are related if they contain common fields. DBMS packages based on the relational model can link data elements from various tables to provide information to users. Limitations of the relational structure: Cannot process large amounts of business transactions as quickly and efficiently as the hierarchical and network models. 9. Why is the object-oriented database model gaining acceptance for developing applications and managing the hypermedia databases at business websites? Multimedia web-based applications for the Internet and corporate Intranets and extranets have become a major application area for object technology. Object-oriented databases are able to handle complex types of data 50 (graphics, pictures, voice, and text) better than other structures. They are relatively easy to use, and they are the key technology being used in multimedia-based applications for the Internet and corporate Intranets and extranets. As well, they support inheritance - new objects can be automatically created by replicating some or all of the characteristics of one or more parent objects. 10. How have the Internet, intranet, extranets, and the World Wide Web affected the types and uses of data resources available to business end users? The Internet and the World Wide Web have greatly affected the types and uses of data resources available to business end users. Users are now able to access massive amounts of data from these resources, which enable them to analyze greater amounts of information in order to make better decisions affecting the organization. VIII. ANSWERS TO APPLICATION EXERCISES 1. Tracking Employee Software Training at Canada AAA Systems a) Build a database table to store the data provided and enter the records shown as a set of sample data. (Note that this table has no natural unique identifier. A combination of the project name, task name, employee ID, and production week is required to uniquely identify a row in this table.) Create a query that will list the hours worked for all employees who worked more than 40 hours during production week 20. Generate a report Grouped by project that will show the number of hours devoted to each task on the project and the total number of hours devoted to each project, as well as a grand total of hours worked. Create a report grouped by employee that will show the hours worked on each task and total hours worked. The used should be able to select a production week and have data for just that week presented. b) c) d) [See Data/Solutions Files] 2. Calculating Training Costs a) If you have not completed Application Exercise 1, complete part a of that exercise now. For this exercise, we will delete the Hours and Category columns from the existing table because they are characteristics of the course and not a particular session, so delete those columns now. Next create a course table with the structure and data shown in the Application Exercise 2 Data Table. Make sure that the Title column in this new table has exactly the same data type and length that you used for the Title column on the previous table. Create and print a listing of a query that joins the two tables based on the common Title column and displays all columns of both tables. Create a report that could be used to bill the costs of each session to the appropriate departments. Each department will be billed only for Unit Costs, so join the tables and multiply unit cost by the number of attendees from each department to get the billing for that department. Include a total to be billed to each department across all training sessions that have been held. Create a report grouped by Course and Category that shows the total cost of each session (Fixed cost + unit Cost * total attendees) and cost per attendee (the above divided by total attendees). b) c) [See Data/Solutions Files] IX. ANSWERS TO REAL WORLD CASES Real World Case 1: IBM versus Oracle: Playing Catch-Up in Database Management 1. What key business strategies did Janet Perna implement to help IBM catch up to Oracle in the database management software market? 51 IBM finally realized how far behind there were in their database development systems such as those built and offered by Oracle and other software developers. As these companies surged ahead, IBM continued to concentrate on only offering mainframe database software. Janet Perna had a number of business strategies that she implemented in order to help IBM compete in developing database software for servers and PCs. The key business strategies that Janet Perna used were: develop and market DB2, a competing database product against Oracle. Perna used a combination of innovative development, a large DB2 sales team, a customer satisfaction focus, and lowball pricing and a marketing strategy to align IBM against its competitors helped them to close the gap. 2. What is the business case for both IBM’s and Oracle’s product strategy for their database software? IBM’s business case was to design their DB2 as an open-ended platform and they are partnering with Oracle’s competitors like Siebel Systems, SAP AG, and PeopleSoft to include DB2 as the database foundation for business applications like CRM and ERP. By doing so, IBM is not developing its own software. Oracle on the other hand is tying its database sales to its e-Business Suite of Business application software in one integrated package that is marketing to all enterprise software users. 3. Which approach would you recommend to a company seeking a database system today? Why? Whatever approach a company takes towards seeking a database system today is dependent on what and how they want their systems to work. The most important aspect is that they must choose a system that meets their needs and affords them as much flexibility as possible. Support of the system is also critical, and its easy of implementation and use is also very important. Data mining is critical to success and competitive advantage; therefore a system must have this capability. Any organization does not need a complex system that is difficult to integrate and use. What they need is a system that meets their needs and helps them to run their business. Real World Case 2: Canadian Blood Services: Donor Data Management 1. What are the benefits of business intelligence for businesses such as Canadian Blood Services? Business intelligence (BI) is the gathering, managing, analyzing and sharing of information in order to gain insights that can be used to make better decisions on an enterprise wide basis. At CBS, the advantage of using BI stems from the potential to combine advanced techniques such as data warehousing, data mining, and decision support in order to transform information into powerful customer relationship management systems that can help create stronger, more profitable relationships, identify new business opportunities. 2. How does BI make use of available databases? The available databases are shared across the enterprise through internet based technologies and this seamless sharing of information results in expedient and efficient business decisions throughout the organization. BI systems rely on three key tracking and storage technologies: Data Warehousing, Data Marts, and Online Analytical Processing. Data Warehousing involves the coordinated and periodic copying of data from a variety of sources (both internal and external) to an environment optimized for analytical processing. Data Marts offer a subset of information from a warehouse relevant to a specific department or small group of users. OLAP (Online Analytical Processing) allow users to view and analyze stored data across multiple dimensions. 3. What is the significance of a Web-based BI system? 52 A web based BI system standardizes the front-end interface and the communication technologies that are used across the company for accessing the BI databases. The browser based front end allows the creation of an Intranet, moreover an Enterprise Information Portal that provides universal access to view and use corporate data. Furthermore, the authoring, publishing and sharing of hypermedia documents makes updating and sharing of information faster. Real World Case 3: Shell Exploration and Others: Using Data Warehouses for Data Resource Management 1. Why do companies still have problems with the quality of the data resources stored in their business information systems? Many companies still have problems with the quality of the data resources stored in their business information systems because of the inaccuracy of the data itself. Foe example, the majority of databases have problems such as redundant data, wrong data, missing data, and miscoded data. As well, many companies are still very much focused on the business processes involved in the data rather than on the form and congruity of the data. IT departments often do not have the time, resources, or personnel to cleanse, reconcile, and integrate data from the various data silos found throughout the company. 2. How do data warehouse approaches help companies like Shell and OshKosh meet their data resource management challenges? Data warehouse approaches help companies like Shell and OshKosh to meet their data resource management challenges by combining and integrating data from a number of sources into one database system. Shell used a tool from Kalido Ltd to analyze and map the data from various systems and then combine it into one warehouse. Managers at Shell were quick to realize the added value of this approach to database collection and storage. OshKosh decided not to avoid using data warehouses from ERP suites. Instead, they decided to create a homegrown IBM DB2 warehouse that unified data from different applications. Programmers at OshKosh were able to create tags that reconciled incoming data elements in order to capture data that otherwise may have been missed. 3. What business benefits can companies derive from a data warehouse approach? Use CompUSA as an example. Business benefits that companies such as CompUSA can derive from a data warehouse approach include the simple fact that in information today is what makes organizations competitive. Data generated through good clean data in data warehouses enables managers to make better decisions. Data mining and data warehousing is big business. Information is continually analyzed and mined by sales agents in order for them to identify leads on good prospects for CompUSA warranties and other products. 53