1. 7 7 Chapter 7 The University Lab: Conceptual Design Database Systems: Design, Implementation, and Management 4th Edition Peter Rob & Carlos Coronel

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3. 7 7 Database Initial Study 4Key Users of the UCL Application u The lab director u The lab assistants u The secretary of the CIS department 4UCL Objectives u Provide users with controlled access to the UCL’s assets. u Guide users working with UCL’s assets and provide general problem-solving services.

4. 7 7 Figure 7.1 The University Computer Lab’s Organizational Structure

5. 7 7 Database Initial Study u Inventory/storage/order management u Equipment maintenance and repair management u Equipment check-out and check-in management u Lab assistant payroll management u Lab reservations management u Computer lab access management

6. 7 7 Database Initial Study 4UCL’s Operations u Inventory/storage/order management l Classes of UCL’s inventory items –Hardware –Software –Literature –Supplies l Each inventory item is classified by inventory type in a four-part hierarchy: category, class, type, and subtype. (Table 7.2) u Non-serialized vs. serialized items. u Inventory’s items are updated when: l An ordered item is received. l An item is checked out or checked in. l A consumable item is withdrawn. l Inventory adjustment is needed.

7. 7 7 Inventory Type Hierarchy Table 7.2

8. 7 7 Database Initial Study u Equipment maintenance and repair management l Maintenance and management information is kept in the Bad Equipment Log and the Hardware Returned for Service Log. u Equipment check-out and check-in management l Check-out form is filled when equipment is checked out. l Notice is sent when the equipment is not returned. u Lab assistant payroll management l Time sheets are used to pay LAs on an hourly basis for a fourteen day pay period. u Lab reservation management l A faculty member fills out a reservation form with date, time, department, and course number of the class. u Computer lab access management l Lab users sign in the users’ log and deposit a University ID card. (Table 7.3)

9. 7 7 A Sample Volume of Information Log Table 7.3

10. 7 7 Database Initial Study 4Problems and Constraints with Current Manual System u Never up-to-date and prone to errors. u Too much data duplication and data inconsistency. u Incapable and impractical to generate useful information. u Incapable of ad hoc queries. u Too much time spent on manual data processing. u Difficult inventory data management.

11. 7 7 Database Initial Study 4Areas of Operational Problems u Inventory/Storage/Order Management l The CLD does not have ready access to crucial inventory manage data. l The UCL needs to know the available stock and average use of suppliers to effectively manage the inventory. l The CLD does not always know the actual location of any item at any given time. u Equipment maintenance and repair management l The CLD cannot easily generate repair and maintenance history for each piece of equipment. l The CLD cannot easily determine the status of items currently subject to maintenance procedures.

12. 7 7 Database Initial Study u Equipment check-out/check-in management l The CLD lacks timely and correct information about the Lab assets. u Lab assistant payroll management l The CLD spends too much time reconstructing summaries of hours worked by each LA. l The CLD cannot easily estimate student work loads. u Lab reservations management l The manual reservations system is inadequate. l The current system does not provide statistical information useful for scheduling Lab reservations. u Computer lab access management l The user log is not properly maintained. l Some students do not return certain items. l Increasing security problems are a major concern.

13. 7 7 4Constraints u Time Frame l The new system needs to be fully operational within 3 months. u Hardware and Software l It must be developed with existing UCL hardware and software. It must run on the existing LAN. u Distributed Aspects and Expandability l It must be able to operate within a multi-user environment. l Its operation will be independent of existing administrative systems on campus. u Cost l The programming costs must be minimal. l The new system will use no more than two additional terminals. l It must operate without requiring additional personnel. l CIS department has set aside $9,500. Database Initial Study

14. 7 7 4System Objectives u General objectives u Specific objectives 4General System Objectives u Improve operational efficiency, thereby increasing the UCL’s capability and its ability to expand its operations. u Provide useful information for planning, control, and security.

15. 7 7 4Specific System Objectives u Inventory/storage/order management l Provide better control of purchase orders. l Monitor the stock of supply items. l Control inventory by type (group) as well as by individual item. l Provide quick and efficient information about the location and status of each individual item. l Provide timely information about the use of supplies and generate the statistical information. Database Initial Study

16. 7 7 u Equipment maintenance and repair management l Monitors the maintenance history of each item. l Tracks items that have been returned to the vendor for repair or replacement. u Equipment check-out/check-in management l Tracks the items that are checked out. l Monitors the item check-out time. l Generates usage statistics for reference purposes. u Lab assistant payroll management l Provides scheduling and work load information. l Provides work summaries for each LA.

17. 7 7 Database Initial Study u Lab reservations management l Decrease the time spent processing a reservation. l Produce reservation schedules. l Generate statistical summaries by department, faculty, staff member and date. u Computer lab access management l Provide tighter control over users and resources in the Lab. l Reduce the sign-in time. l Provide information about peak use times for scheduling purposes.

18. 7 7 4Scope and Boundaries u What will be the system’s extent? l It will cover only the CIS portion of the organizational chart presented in Figure 7.1. l It will be independent of other database systems currently used on campus. u What operational areas will be covered by the system? l It will cover the six operational areas (see section 7.1.3) and will address the specific objectives listed in section 7.1.5. –Inventory/storage/order management –Equipment maintenance and repair management –Equipment check-out/check-in management –Lab assistant payroll management –Lab reservations management –Computer Lab access management Database Initial Study

19. 7 7 u What design and implementation strategy should be adopted to bring the system online within the specified time constraints? u What modules must be included in the system? Database Initial Study Table 7.4 Required UCL System Modules

20. 7 7 u How do the modules interface? Database Initial Study Figure 7.2 The University Computer Lab Management System

21. 7 7 Conceptual Design 4Information Sources and Users u Conceptual design begins with confirming good information sources. l Computer Lab director (CLD) l Computer Information Systems (CIS) department secretary and chair l Computer Lab assistants (LA) l Students, faculty, and staff who use the Lab’s resources l All current computer lab forms, file folders, and report forms

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23. 7 7 Conceptual Design 4Information Needs: User Requirements (General System Requirements) u The system must be easy to use. u The system must provide security measures by using passwords and access rights. u The system must be fully integrated, thus eliminating redundant data entry and updates. It must ensure database integrity. u Users must be able to access the system concurrently from several workstations. (See Table 7.6 and Figure 7.3 )

24. 7 7 Workstation Assignments: Uses and Users Table 7.6

25. 7 7 University Computer Lab Management System: A Setup Summary View Figure 7.3

26. 7 7 Conceptual Design u The system processes must perform the following functions: l PERSONNEL process l INVENTORY and storage process l ORDER process l MAINTENANCE process l RESERVATION process l CHECK_OUT process l ACCESS process u The system’s input requirements are driven by its output requirements. (See Table 7.7)

27. 7 7 UCLMS Reports Table 7.7

28. 7 7 Conceptual Design 4Developing the Initial Entity Relationship Model

29. 7 7 Business Rule 1: Each item belongs to only one inventory type, and each inventory type may have zero, one, or many items belonging to it. Conceptual Design Table 7.9 An Example of Inventory Type

30. 7 7 The E-R Model Segment For Business Rule 1 Figure 7.4

31. 7 7 Business Rule 2: An item may be placed in use upon its arrival, or it may be stored. Some items may be stored in more than one location. Therefore, an item may be stored in zero, one, or more locations. Each storage location may store zero, one or many items. Conceptual Design

32. 7 7 The E-R Model Segment For Business Rule 2 Figure 7.5

33. 7 7 Business Rule 3: An order references only one vendor, and each vendor may have zero, one, or many orders. Conceptual Design Figure 7.6 The E-R Model For Business Rule 3

34. 7 7 Business Rule 4: Each order contains one or many ordered items. Conceptual Design Figure 7.7 The E-R Model Segment For Business Rule 4

35. 7 7 Business Rule 5: Each ordered item corresponds to one inventory type. Conceptual Design Figure 7.8 The E-R Model Segment For Business Rule 5

36. 7 7 Business Rule 6: Each item may require zero, one, or many repairs. Conceptual Design Figure 7.9 The E-R Model Segment For Business Rule 6

37. 7 7 Business Rule 7: Each item to be repaired may or may not be returned to the vendor, and each vendor may have zero, one, or many repair items returned. Conceptual Design Figure 7.10 The E-R Model Segment For Business Rule 7

38. 7 7 Business Rule 8: Each user may check out zero, one, or many items, and each item may be checked out by zero, one, or many users during the semester. Conceptual Design Figure 7.11 The E-R Model Segment For Business Rule 8

39. 7 7 Business Rule 9: Each (faculty or staff) user may withdraw zero, one, or many items, and each item may be withdrawn by zero, one, or many users during the semester. Conceptual Design Figure 7.12 The E-R Model Segment For Business Rule 9

40. 7 7 Business Rule 10: Each (student) user may sign into the user log many times during the semester. Conceptual Design Figure 7.13 The E-R Model Segment For Business Rule 10

41. 7 7 Business Rule 11: Each (faculty) user may place zero, one, or many reservations during the semester. Conceptual Design Figure 7.14 The E-R Model Segment For Business Rule 11

42. 7 7 Business Rule 12: Each reservation is recorded by an LA, and each LA may record zero, one, or many reservations during the semester. Conceptual Design Figure 7.15 The E-R Model Segment For Business Rule 12

43. 7 7 Business Rule 13: Each LA is assigned to work at least one day in each week’s work schedule. Conceptual Design Figure 7.16 The E-R Model Segment For Business Rule 13

44. 7 7 Business Rule 14: Each LA accumulates hours worked during each two- week pay period. Conceptual Design Figure 7.17 The E-R Model Segment For Business Rule 14

45. 7 7 Business Rule 15: Each item is supplied by a specific vendor, and each vendor may supply several different items. Conceptual Design Figure 7.18 The E-R Model Segment For Business Rule 15

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47. 7 7 Figure 7.19