Consider The List Of Individual 3NF Relations Below
Consider The List Of Individual 3nf Relations Below These Relations W
Consider the list of individual 3NF relations below. These relations were developed from several separate normalization activities.
PATIENT(Patient_ID,Room_Number,Admit_Date,Address)
ROOM(Room_Number,Phone,Daily_Rate)
PATIENT(Patient_Number,Treatment_Description, Address)
TREATMENT(Treatment_ID,Description,Cost)
PHYSICIAN(Physician_ID,Name,Department)
PHYSICIAN(Physician_ID,Name,Supervisor_ID)
a. Merge these relations into a consolidated set of 3NF relations. State whatever assumptions you consider necessary (including but not limited to foreign keys) to resolve any potential problems you identify in the merging process.
b. Draw an E-R diagram for your answer
Paper For Above instruction
The process of merging multiple relations into a cohesive set of third normal form (3NF) relations involves careful analysis of the existing relations, their attributes, dependencies, and potential redundancies. In this scenario, we are provided with multiple relations related to healthcare data, some of which appear to have overlapping entities and attributes, which require consolidation while preserving the integrity and normalization of the database.
Analysis of Current Relations and Issues
The relations provided are:
- PATIENT(Patient_ID, Room_Number, Admit_Date, Address)
- ROOM(Room_Number, Phone, Daily_Rate)
- PATIENT(Patient_Number, Treatment_Description, Address)
- TREATMENT(Treatment_ID, Description, Cost)
- PHYSICIAN(Physician_ID, Name, Department)
- PHYSICIAN(Physician_ID, Name, Supervisor_ID)
Firstly, note that there is a duplication of the PATIENT relation: one identified by `Patient_ID` and another by `Patient_Number`. This indicates that they could be representing the same entity with different attribute sets, which needs reconciliation.
Furthermore, the PATIENT relation contains attributes like `Room_Number` and `Address`, suggesting a patient's room assignment and contact details. The ROOM relation provides details regarding the room only, which is appropriate.
The PATIENT relation with `Treatment_Description` indicates a relationship between patients and their treatments but lacks explicit linkage to a Treatment entity, which is provided separately by the TREATMENT relation.
Physicians are represented with duplication as well, with two relations, which should be merged to avoid redundancy.
Assumptions
- Patient Identifiers: It can be assumed that `Patient_ID` and `Patient_Number` reference the same patient entity; thus, we will unify these.
- Treatment Association: Patient-treatment relationships are many-to-many; therefore, a junction relation is needed.
- Physician Management: The physician’s supervisor is also a physician, so `Supervisor_ID` is a foreign key referring to `Physician_ID`, creating a hierarchical structure.
- Foreign Keys:
- `Room_Number` in PATIENT references ROOM.
- A new patient-treatment relationship, e.g., `PATIENT_TREATMENT`, will connect patients and treatments.
- `Physician_ID` in any relations identifies physicians, with `Supervisor_ID` referencing the same.
Merged Relations
Based on the analysis, the consolidated set of relations in 3NF would include:
1. PATIENT(Patient_ID, Name, Address, Room_Number, Admit_Date)
- Merges patient identifiers and contact info.
2. ROOM(Room_Number, Phone, Daily_Rate)
3. TREATMENT(Treatment_ID, Description, Cost)
- Stays as initial, representing treatment details.
4. PATIENT_TREATMENT(Patient_ID, Treatment_ID, Treatment_Date)
- Junction relation for many-to-many relationship between patients and treatments, with the treatment date.
5. PHYSICIAN(Physician_ID, Name, Department, Supervisor_ID)
- Single relation for physicians, with self-referential supervisor relationship.
ER Diagram
The ER diagram for this relational schema would feature:
- Entities: PATIENT, ROOM, TREATMENT, PHYSICIAN
- Relationship: `Receives_Treatment` between PATIENT and TREATMENT through PATIENT_TREATMENT
- Relationship: `Occupies` between PATIENT and ROOM
- Recursive relationship: `Supervises` within PHYSICIAN linking Supervisor_ID to Physician_ID
The diagram visually would represent:
- PATIENT connected to ROOM via `Occupies`.
- PATIENT linked to TREATMENT via PATIENT_TREATMENT.
- PHYSICIAN linked to self via `Supervises`.
This schema encapsulates the core healthcare data with proper normalization and minimal redundancy.
Conclusion
The merging process consolidates overlapping entities and constructs associative entities where necessary, adhering to 3NF principles and ensuring scalability and data integrity. Proper foreign key constraints and self-referential relationships facilitate accurate representation of real-world relationships within healthcare management systems.
References
- Communications of the ACM, 13(6), 377-387.