1.7 KiB
| title | aliases | tags |
|---|---|---|
| i201-practice |
Section A
1
a) sequence diagram - to document a sequence of particpant interactions required to carry out a use case b) 1 - Actor - a participant in the sequence 2 - Activation Bar - indicate when a participant is doing something 3 - message - indicate communication between participats
2
update anomaly - e.g., when a single employee is working on two projects, and we need to update their salary, it is possible to only update their salary in one location causing an update anomaly
root causes - this occired because there was redundancy within the database - the employee and his salary should only be stored in one location
how it can be solved/avoided - this can be easily avoided by normalising the database to remove redundancies.
3
a) business functions are things that the business ought to be doing (not what it is doing now), for example "accept payment from customer". each business function essentially become a fuction or a set of functions within the information system. they do not describe the who, how, or where of the function.
b) business function are typiclaly modelled using use case diagrams. in the final system they become features or a set of features
4
- dont have the technical ability
- not legal
- organisational - lack of institutional will
5
requirements - Requirements are something an information system should do, or some constraint it should adhere to
acceptance tests - not covered
6
use predictive when
- simple requirements
- stable/mature technologiess
- stable environment
- non experimental
7
- how quickly? - requirements should be unambiguous
- shouldn't say how? - requirements hould say what and not how