Course4资讯系统在实务上的应用.ppt

1,Course 4資訊系統在實務上的應用,李鍾斌,2,Introduction,This chapter(Chapter 8)gives examples of how information is used in todays firmsTransaction Processing Systems process data that describe the firms daily operations and produce a database used by other firm systemsA related application is Customer Relationship Management(CRM)CRM uses data warehousing,meaning data accumulates over time and can retrieved for use in decision making,3,THE TRANSACTION PROCESSING SYSTEM,This term TPS is used to describe the IS that gathers data describing the firms activities,transforms the data into information,and makes the information available to users both inside and outside the firm Figure 8.1 is a model of a TPS where data is gathered from the firms physical system and environment,and entered into a database Data processing software transforms the data into information for the firms management and for individuals and organizations in the firms environment,4,5,System Overview,Data flow diagrams(DFDs)are used to document the system in a hierarchical mannerThe diagram in Figure 8.2 represents the highest level,called a context diagram because it presents the system in the context of its environmentThe data flowing from the distribution system to management consists of the standard accounting reports,6,7,The Major Subsystems of the Distribution System,While context diagrams define the system boundary,other DFDs are used to describe the major subsystems in the firms data processesWhen a series of DFDs are used in a hierarchy,they are called leveled DFDsFigure 8.3 which is a Figure 0 diagram showing three major subsystemsThese subsystems are identified by the numbered upright rectangles in Figure 8.3,8,9,Systems That Fill Customer Orders,Figure 8.4 shows the four main systems involved in filling customer orders:The order entry system enters customer orders into the system The inventory system maintains the inventory records The billing system prepares the customer invoices,and The accounts receivable system collects the money from the customers Figure 8.4 expands Process 1 shown in the Figure 0 diagram,and is called a Figure 1 diagram,10,11,Systems That Order Replenishment Stock,The subsystems concerned with ordering replenishment stock from suppliers are shown in Figure 8.5,which is called a Figure 2 diagram since it explodes Process 2 of the Figure 0 diagram The purchasing system issues purchase orders to suppliers for the needed stock The receiving system receives the stock,and The accounts payable system makes payment,12,13,Systems That Perform General Ledger Processes,Figure 8.6 shows the detail for the last of the three processes in the Figure 0 diagramThe general ledger system is the part of the accounting system that combines data from other accounting systems to present a composite financial picture of the firm.Two subsystems are involved:The update general ledger system posts records that describe the various actions and transactions to the general ledgerThe prepare management reports system uses the contents of the general ledger to prepare the balance sheet and income statement,14,15,ORGANIZATIONAL INFORMATION SYSTEMS,Other specialized information systems used in a firm include the marketing information system(MKIS)and the human resources information system(HRIS)Another IS that is implemented at the organizational level is the executive information systems(EIS),used by upper level managers in an organizationThe MKIS,HRIS,and EIS are described below.,16,The Marketing Information System,An MKIS is made up of input and output subsystems connected by a database(Figure 8.7)The Input Subsystems are:Transaction processing systemThe marketing research subsystem The marketing intelligence subsystemEach output subsystem provides information about four critical elements in the marketing mix:The product subsystemThe place subsystemThe promotion subsystemThe price subsystem,17,18,The Human Resources Information System,Figure 8.8 illustrates the human resources information system(HRIS)The figure shows three main HRIS input subsystems:The transaction processing system provides input data The human resources research subsystem used for gathering specialized research informationThe human resources intelligence subsystem that gathers environmental data that bears on HR issues,19,20,The Executive Information System,The executive information system(EIS)provides information to top-level managers on overall firm performance.A firms EIS usually includes executive workstations networked to a central server(shown in Figure 8.9)Some executives prefer more detail,so EIS designers build in flexibility so their systems fit the preferences of all executives,whatever they are One approach is to provide a drill-down capability,giving executives the ability to bring up a summary display and then display successively greater levels of detail(Figure 8.10),21,22,23,CUSTOMER RELATIONSHIP MANAGEMENT(CRM),CRM systems are used to manage relationships between a firm and its customers so both can receive maximum value from the relationship Using more effort to cultivate long-term client relationships makes good marketing sense since its usually cheaper to keep existing customers than to obtain new onesThe CRM system accumulates customer data over a long period and uses the data to produce information for users.A CRM systems central element is the data warehouse,24,DATA WAREHOUSING,Until recently,computer technology could not support a system with such large-scale data demands The term data warehouse was coined to describe a data store with the following characteristics:Very large scale storage capacityThe data is accumulated into new records instead of updating existing records with new informationThe data is easily retrievable.The data is used for decision making,not for the firms daily operations,25,The Data Warehousing System,A data warehousing system(Figure 8.11)enters data into the warehouse,transforms the data into information,and makes the information available to users Data is gathered from data sources and goes through a staging area before being entered in the warehouse data repositoryAn information delivery system obtains data from the warehouse data repository and transforms it into information for the users The data warehousing system also includes a management and control components,26,27,How Data Is Stored in the Warehouse Data Repository,The warehouse data repository stores two types of data in separate tables,which are combined to produce an information packageIdentifying and descriptive data are stored in dimension tables(Figure 8.12)Fact tables contain the quantitative measures of an entity,object,or activity(Fig.8.13)An information package identifies all of the dimensions that will be used in analyzing a particular activity.Figure 8.14 shows the format and Figure 8.15 includes some sample data,28,29,30,31,32,The Star Schema,The key that identifies the dimension and provides the link to connect the dimension tables to the fact table is called a star schema Figure 8.16 shows how the keys in four dimension tables are related to keys in the information package in the centerFig.8.17 is an example using the four dimension tables:customer,time,salesperson,and productThe warehouse data repository contains multiple star schemas one for each activity type to be analyzed,33,34,35,INFORMATION DELIVERY,The final element in the data warehousing system is the information delivery systemInformation is obtained from the data repository,transformed into information,and made available to users Figure 8.18 shows how the user can navigate the data repository to produce summary information,detailed information,and detailed dataFigure 8.19 shows the results of a drill-across navigation,producing outputs in different hierarchies,36,37,38,線上分析系統(ONLINE ANALYTCAL PROCESSING),OLAP is a type of software especially developed for data warehousesUsing OLAP,users can communicate with the data warehouse either through a GUI or Web interface,and quickly produce information in a variety of forms,including graphics There are two approaches to OLAP(Figure 8.20):關連式線上分析系統 ROLAP(for relational online analytical processing)that utilizes a standard relational DBMS多維度線上分析系統 MOLAP(for multidimensional online analytical processing)that utilizes a special multidimensional DBMS,39,40,ROLAP and MOLAP,Both OLAP types include a data warehouse server and a second server that houses OLAP software A major difference is that the MOLAP workstation includes a downloaded multidimensional database The data in this database has already been formatted in various dimensions so that it may be made available quickly rather than go through time-consuming analyses Figure 8.21 illustrates a report that is the type that ROLAP can easily prepareMOLAP can produce information in many dimensionsFigure 8.22 illustrates a summary report in four dimensions:store type,product,age,and gender,41,42,43,資料探勘 DATA MINING,Data mining is the process of finding relationships in data previously unknown to the userData mining helps users discover relationships and present them in an understandable way so the relationships can be used in decision makingThe two basic data mining techniques are:Hypothesis Verification where data is used to test theoriesKnowledge Discovery in which users search for common characteristics within the data,