DB Design Methodology- 1A Database Design MethodologyArea of application:Design of database with its applications.Perspective:The method assumes that the primary purpose of the future system is toautomate current or planned activities of the enterprise.The method assumes (as do all database design methodologies) that dif-ferent views on the enterprise, conflicts, and political differences will beresolved during the database design process.Life-Cycle:The life-cycle comprises the following steps:Project Progress Report: Phase IgI.1. Environment & Requirement AnalysisgI.2. System Analysis & SpecificationProject Progress Report: Phase IIgII.1. Conceptual ModelinggII.2. Logical ModelinggII.3. Task EmulationgII.4. Optimization (NOT REQUIRED for the 424 project)Project Progress Report: Phase IIIgIII. ImplementationgIII.1 Convert Emulated tasks to codegIII.2 Bulk-Loading & Tuning (LIMITED for the 424 project)gIII.3 TestingLimitation:The methodology does not cover implementation, testing, maintenance,and project management.DB Design Methodology- 2ExampleDesign a Merryland State Motor Vehicle Administration (MVA) Informa-tion SystemThe system must support all activities of the Merryland State MVA.The tasks of the MVA include maintaining all information pertaining to:vehicle emissions, license maintenance, vehicle registration maintenance,fine and fee maintenance, driving record maintenance and report genera-tion.Etc., etc., ...DB Design Methodology- 3I.1. Environment & Requirements AnalysisThe purpose of this phase is to investigate the information needs of and theactivities within the enterprise and determine the boundary of the designproblem (not necessarily identical to the boundary of the future computerizedsystem, if any).Input:Information describing the current status of the enterprise, possibleinefficiencies, plans for the future, and constraints that have to be satisfiedin conducting business.Output:A Top-Level Information Flow Diagram describing the major docu-ments and functions, and the boundary of the design problem. The docu-ments include the major input, output, and internal documents. Thefunctions model the major activities within the enterprise.Function:To collect the information about the enterprise and design the top-levelinformation flow diagram.DB Design Methodology- 4Guidelines:gTechniques: collect information by contacting interviews of people at alllevels of the organization; analyze questionnaires; review short and longterm plans, business manuals, files, forms, etc.Tools: express a top-level information flow diagram to capture the func-tions and important documents of the enterprise, and to start the designwith the i/o documents and work from the outside in towards a "top-level"design.The tool we use for designing the top-level information flow diagram isthe following graphic formalism for representing structures andprocesses:structureprocessinformation flowgTwo structures are never directly connected.gTwo processes are never directly connected.DB Design Methodology- 5PersonalPEIInformationDRTDriving RecordMaintenanceReportsRPTLMTLicenseMaintenanceETTEmmissionsTestingFFTFine and FeeMaintenanceRMTRegistrationMaintenanceInformationOwnerInformationVehicleInformationPaymentInformationUnpaid FineInformationDriver LicenseInformationDriver RecordScheduleViolationScheduleFeeOWIVHIPRIUFIDLIDRIVSIFSIWarningPointsReportDriving RecordCitationViolationRequestDriving RecordRequestViolat. ChangeVCE RQE DRE CTE PWEStatisticsYearlyAccountingMonthlyBad RecordsMonthlyLicenseDriver’sNoticeLic. RenewalApplicationLicenseTest NoticeEmmisionsETELAELRELIEMBEMAEYSEVQEVehicle ReportRequestFCEFPELPEFSETSERCERRERAEVREVehicleReportRegistrationApplicationReg. RenewalNoticeRegistrationCardTag andStickerFee ScheduleReportLate PaymentNoticeFinePaymentFee ChangeRequestMVA Top-Level Information Flow DiagramDB Design Methodology- 6I.2. System Analysis & SpecificationThe purpose is to divide the functions from the Top-Level Information FlowDiagram hierarchically into tasks. The tasks should be reasonably indepen-dent to minimize the task-to-task interfaces (documents).During the division process, the documents used by each function are alsobroken down. The process is continued until each task is small enough to beclearly understood, and until each document can be conveniently expressed interms of data elements that cannot be further divided.The result is a detailed Task Flow Diagram and a set of forms describing thedocuments and the tasks.Input:The Top-Level Information Flow Diagram and information about thedocuments and functions from phase 1.Output:Task Forms; Document Forms; Document and Data Usage Matrices; and,the detailed Task Flow Diagram.Function:Decompose functions and documents. Specify the resulting Task andcomponent Document Forms. Specify Document and Data UsageMatrices. Design detailed Task Flow Diagram.Guidelines:gTechnique: top-down hierarchical decomposition.gTools: Task Forms; Document Forms; Usage Matrices; and the graphicalformalism for Task Flow Diagrams.DB Design Methodology- 7Examples of Task FormsTASK NUMBER: LMTTASK NAME: License MaintenancePERFORMER: Driver registration staffPURPOSE:Maintain all driver licensing informationENABLING COND:Receipt of License Application (LAE); Receipt ofLicense Renewal Notice (LRE); First day of eachmonth; Last day of each month;DESCRIPTION:Issue new licenses and process renewals. Printrenewal notices on a monthly basis. Delete expiredlicenses on a monthly basis.FREQUENCY: See subtasks (different for each subtask!)DURATION: See subtasks (different for each subtask!)IMPORTANCE: See subtasks (different for each subtask!)MAXIMUM DELAY: See subtasks (different for each subtask!)INPUT:(DLI) Driver License Infor; (FSI) Fee Schedule;(LAE) License Application; (LRE) LicenseRenewal Notice; (PEI) Person InfoOUTPUT:(DLI) Driver License Info; (ENE) Expiration No-tice; (LIE) Driver’s License; (LRE) LicenseRenewal Notice; (PEI) Person Info; (PRI) PaymentRecordDOCUMENT USE:(DLI) all columns; (LIE) all columns; (LAE) allcolumns; (PEI) all columns; (FSI) all columns;(PRI) all columns; (LRE) all columns; (ENE) allcolumnsOPS PERFORMED: See subtasksSUBTASKS:(LMT.1) NEW-LICENSE; (LMT.2) RENEW-LICENSE; (LMT.3) PRINT-RENEWAL-NOTICES; (LMT.4) DELETE-EXPIRATIONSERROR COND: See subtasksDB Design Methodology- 8Examples of Task FormsTASK NUMBER: LMT.1TASK NAME: NEW-LICENSEPERFORMER: Driver Registration StaffPURPOSE:Issue a license to a previously unlicensed driver,
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