Corresponding to Problem and Exercise 7.35. Refer to the attached Adobe PDF docu
ID: 3602784 • Letter: C
Question
Corresponding to Problem and Exercise 7.35. Refer to the attached Adobe PDF document, NOT the textbook’s Figure 7-23 on page 215. The Context DFD and Level-0 DFD depict a university class registration system. Identify and explain potential violations of rules (Tables 7-2 and 7-3) and guidelines (pg. 189) on these diagrams. There are 5 errors.
Here are some exceptions in the diagram that are NOT errors (if you list them, they will NOT count as an error): • While the Context DFD is always numbered zero (as the attached diagram is), the text shows Level-0 DFDs with processes numbered as 1.0, 2.0, etc. (i.e., a decimal number with a .0). That the attached diagram has processes numbered without a X.0 format is NOT an error. • The text shows Gane and Sarson process symbols with a line drawn about 20% from the top, with that section shaded in. That the attached diagram doesn’t is NOT an error (indeed, MS Visio doesn’t draw them that way). • The text shows Gane and Sarson data store symbols also with a line drawn about 25% from the left of the symbol, with that section shaded in. That the attached diagram doesn’t is NOT an error.
Problem 2: CONTEXT DFD Course 0 Class Registration System Student Department List of Classes Class Schedule Problem 2: Level-0 Diagram Class Schedule Course Request Student Student Receive Course Request Check for Availability Course Request Possible Classes List of Classes Scheduled Classes Department Receive D1 Class Roster Courses Lists List of InstructorsExplanation / Answer
Error 1 : We can't make an entity two times in any level diagram, no. of entities in the Context Level diagram should be equal/same in all other level's DFD. Here in Level 1 DFD,Student Entity is placed 2 times.so this is the error.
Error 2 : In context level DFD , only one data flow is going from Department Entity to Process,but in Level 1 DFD,how 2 data flows are going from Department entity to process,if 2 data flows, then it should also be mentioned in context level DFD.
Error 3 : class schedule is illogical Data flow from process 3 to student Entity because if scheduled class is checking for availability,then class schedule is illogical to write.(Hey,you can also think about this). Data flow's name should be enough capable to define the class availability.
Error 4 : Name of Data Flows are same to/from process 1 i .e course Request ,, both name should be different.
Error 5 : As the name of the process 2 is that Receive Course Lists ,, all the data flows to this process are not able to define the correct process meaning,,if the process is Receive Course Lists ,then it should receive a data flow which is named/capable to define/give the Course Lists.