An Event occurs at a single timeslot, but many events can occur at the same time (with seperate students and staff). Thus the 1:1 relationship of "is-at" is not correct. According to the specification, "each event will have exactly one member of staff", yet "teaches" is 1:N meaning that many staff members can be associated with a single event.
An Event occurs at a single timeslot, but many events can occur at the same time (with seperate students and staff). The 1:N relationship of "is-at" supports this. According to the specification, "each event will have exactly one member of staff". "teaches" is N:1 meaning that one event can only be involved with a single staff member, so the specification is met.
An Event occurs at a single timeslot, but many events can occur at the same time (with seperate students and staff). Thus the 1:1 relationship of "is-at" is not correct. According to the specification, "each event will have exactly one member of staff", yet "teaches" is 1:N meaning that many staff members can be associated with a single event.
An Event occurs at a single timeslot, but many events can occur at the same time (with seperate students and staff). The 1:N relationship of "is-at" supports this. According to the specification, "each event will have exactly one member of staff", yet "teaches" is 1:N meaning that many staff members can be associated with a single event.
An Event occurs at a single timeslot, but many events can occur at the same time (with seperate students and staff). Thus the 1:1 relationship of "is-at" is not correct. According to the specification, "each event will have exactly one member of staff". "teaches" is 1:1, so meets the specification. However, each member of staff will have to teach more than a single event, so a N:1 relationship is required here.
A timetable database is required for a University Department. Each taught event is part of a module, each event will have exactly one member of staff associated and several individual students. Each event takes place in a single weekly time slot. Each time slot has a day of the week and a time of day associated.
Select the most appropriate ER diagram for the above scenario:
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