Just did a question on Reltionships and E/R modelling and was hoping for somebody to look over it and show me how I could improve my answer..please.
Figure 1: Proposed database schema (physical model) for a timetable database system.here
Figure 1 shows a sample database schema for a timetable system. It could be said to represent a “physical model” of the system. Using the E/R (Entity/Relationship) modelling technique, draw a logical model of the same system. Your diagram must:
• Accurately reflect what is happening in the real world.
• Give names for the relationships between the entities involved, which accurately reflect what is happening in the real world.
• Correctly model a total (or mandatory) relationship. (Your answer must use an example business rule (or requirement) to support your description (i.e. 2 marks).)
• Correctly model a partial (or optional) relationship. (Your answer must use an example business rule (or requirement) to support your description (i.e. 2 marks).)
(At any point, you may write down a set of assumptions or an explanation if you feel it better clarifies, or justifies your answer).
My answer is here
I basically converted the entity names to singular and uppercase. I inserted names on the relationship lines along with directions..
My two example business rules are:
- All lecturers must teach at least 1 class and no more than 4
- Not all time slots must be filled.
Thanks in advance guys..exam is coming pretty close now