Tài liệu Activity 7.2: Determining Data Integrity Implementations doc

Activity 7.2: Determining Data Integrity Implementations In this activity, you will evaluate a physical design for the Ferguson and Bardell, Inc. case study and then determine areas within the physical design where data integrity requirements and business rules should be implemented with the methods presented in Module 7, “Implementing Data Integrity.” Objectives After completing this activity, you will be able to: ! Identify areas where data integrity should be enforced. ! Choose a method for implementing business rules and data integrity requirements. Before You Begin This activity will take place in small groups, with a class discussion following the activity. Prerequisite To complete this activity, you will need the: ! Completion of Activity 7.1. Time to complete this activity: 30 minutes 44 Activity 7.2: Determining Data Integrity Implementations Exercise 1: Determining Integrity Implementations In this exercise, you will examine the physical design provided, determine areas in the design where data integrity should be enforced, and determine how it should be enforced. ! Identify areas where data integrity should be enforced 1. Join the group to which the instructor assigned you. 2. With your group, study the physical data design on the next page. 3. Based on the business rules and data integrity requirements specified in Activity 7.1, identify how the data integrity requirement can be implemented for each rule in the following table. 4. Supply a reason for each answer in the table. Data integrity rule Implementation Description Timesheet must contain an existing employee, client, job, and task. Contract cannot exist without a valid employee and client relation. Each job entry must have an associated task assignment. Job cannot be created without a default task. Valid date must be specified for each timesheet and for each time entry that a consultant makes. All consultants’ expenses must be formatted correctly, and they must be a positive amount. Employee billing rate must be updated. When you have finished, you will discuss your findings with the class. Activity 7.2: Determining Data Integrity Implementations 45 TypeID (FK) (N)Int FirstName VChar 25 MiddleInitial VChar 2 LastName VChar 25 Address1 VChar 40 Address2 VChar 40 City VChar 30 State VChar 20 Zip VChar 10 SSN VChar 9 E-Mail VChar 50 Salary Currency BillableRate Currency EmployeeID (PK) Int Employee ClientID (FK) (N)DInt EmployeeID (FK) (N)Int JobID (FK) (N)DInt TaskID(FK) (N)DInt Date Date Expenses Currency TotalHours Float BillableHours Float Description VChar 255 TimesheetID (PK) DInt Timesheet ClientID (FK) (N)DInt TimesheetID (FK) (N)DInt Date Date Amount Currency Work Description VChar 255 InvoiceID (PK) DInt Invoice Name VChar 60 Address1 VChar 40 Address2 VChar 40 City VChar 30 State VChar 20 Zip VChar 10 ClientID (PK) DInt Client EmployeeID (FK) Int Make VChar 100 Model VChar 100 VIN VChar 30 Year Date BeginMileage Int EndMileage Int VehicleID (PK) Int Vehicle Is Issued 1 Completes 1 1 ∞ ∞∞ ∞ Is Sent To 1 0 ∞ ∞∞ ∞ 1 1 ∞ ∞∞ ∞ JobDesc VChar 255 JobID (PK) DInt Job TaskID (FK) DInt JobID (FK) DInt JobTask_Link Has Bills Time To VehicleID (FK) (N)Int MaintenanceCost Currency MaintenanceDesc VChar 255 MaintenanceDate Date MaintenanceMiles Int MaintID (PK) Int VehicleMaint Can Have 0 ∞ ∞∞ ∞ 1 1 1 ∞ ∞∞ ∞ TypeDesc VChar 255 TypeID (PK) Int EmployeeType Is Classified As 1 1 1 ∞ ∞∞ ∞ 1 1 ∞ ∞∞ ∞ ClientID(FK) DInt EmployeeID(FK) Int StartDate Date EndDate Date Description VChar 255 ContractID(PK) DInt Contract Purchases 1 1 0 ∞ ∞∞ ∞ Is Made From Contracts With TaskDesc VChar 255 TaskID (PK) DInt Task Has 1 ∞ ∞∞ ∞ 1 0 ∞ ∞∞ ∞ VehicleID (FK) Int EmployeeID(FK) Int Vehicle_Link Can Be Assigned To 0 ∞ ∞∞ ∞ 1 Bills Time To 1 ∞ ∞∞ ∞ 1 THIS PAGE INTENTIONALLY LEFT BLANK . this activity, you will need the: ! Completion of Activity 7. 1. Time to complete this activity: 30 minutes 44 Activity 7. 2: Determining Data Integrity. Activity 7. 2: Determining Data Integrity Implementations In this activity, you will evaluate a physical design