Defense A1

Assignment Reference

Assignment 1 — DB Modeling

Design a physical data model for one of the subject areas assigned to you.

Requirements:

• Model must be in 3NF (no partial or transitive dependencies)
• 8–15 tables
• At least one many-to-many relationship via a junction/bridge table with correct PKs and FKs
• All relationships graphically shown with correct cardinality
• Correct and appropriate data types for all columns
• PKs, FKs, NOT NULL, UNIQUE constraints specified where appropriate
• Clear, meaningful, and consistent table/column names

Model Template to fill in:

• 1.1 Logical Scheme — ER diagram image
• 1.2 Objects — table descriptions with field names, types, constraints, relationship comments
• 1.3 Example data — at least 3 sample rows per table

Submission folder: TASK 1 Modeling — contains modeling_schema.img and model_template.docx

Grading Rubric

Verification Questions

The instructor may ask any of the following during the defense:

1. Walk me through your ER diagram — explain what each table represents and how they relate.
2. Point to the many-to-many relationship in your diagram. Explain why you implemented it with a junction table.
3. Why did you choose this data type for [column]? What would happen if you used a different type?
4. Which columns have NOT NULL and why? Which columns allow NULL, and is that intentional?
5. Explain 3NF in your own words. Show me that your model satisfies it.
6. What is a primary key? Point to the PKs in your schema.
7. What is a foreign key? Show me two tables that are connected by a FK.
8. What does the cardinality label on this relationship mean?
9. If I wanted to add [new entity] to your model, which tables would change and how?
10. Show me the sample data for [table]. How does it relate to data in [related table]?

Submission Checklist

Students must have the following ready before the defense begins:

• TASK 1 Modeling folder is accessible and open
• modeling_schema.img — ER diagram image is visible and legible
• model_template.docx — template is fully filled in (all three sections)
• All 8–15 tables are described in the template
• Sample data (minimum 2 rows per table) is filled in
• Many-to-many junction table is clearly identifiable in both the diagram and the template
• Student can explain every design decision without reading from notes