Question

1.Dormitory management system at a campus
A.create entity and their attributes
B.identify the degree of their relationship
C.identity their cardinalities
D.constraints

Answer 1

A.
1. Dormitory:
- Dormitory name (attribute)
- Dormitory address (attribute)
- Dormitory capacity (attribute)

2. Student:
- Student ID (attribute)
- Student name (attribute)
- Student age (attribute)
- Student gender (attribute)

3. Room:
- Room number (attribute)
- Room capacity (attribute)
- Room type (attribute)

4. Bed:
- Bed number (attribute)
- Bed type (attribute)

B.
- Dormitory and Room have a one-to-many relationship. One dormitory can have multiple rooms, but each room belongs to only one dormitory.
- Room and Bed have a one-to-many relationship. One room can have multiple beds, but each bed belongs to only one room.
- Dormitory and Student have a many-to-many relationship. One dormitory can have multiple students, and one student can be assigned to multiple dormitories.

C.
- Dormitory cardinality: One dormitory to many rooms; Many dormitories to many students.
- Room cardinality: One room to many beds; Many rooms to one dormitory.
- Bed cardinality: One bed to one room; One bed to one student.
- Student cardinality: Many students to many dormitories; One student to one bed.

D. Constraints:
- The number of students assigned to a dormitory cannot exceed its capacity.
- Each student can be assigned to only one bed.
- Each bed can accommodate only one student.
- The number of beds in a room cannot exceed its capacity.
- The number of rooms in a dormitory cannot exceed its capacity.