DATABASE_SCHEMA

Category: 02. Non-AI / Traditional Software
Section: Phase 2: Technical Blueprint

Act as a senior database engineer.
Using the PRD and System Architecture below, design the database schema for a software hackathon project.

PRD: [PASTE PRD]
ARCHITECTURE: [PASTE SYSTEM_ARCHITECTURE]

Provide:
1. Tables (Users, Sessions, Core Entities, Lookup Tables)
2. Columns
3. Data types
4. Primary keys
5. Foreign keys
6. Relationships (One-to-Many, Many-to-Many)
7. Required fields
8. Optional fields
9. Indexes where useful
10. Example records
11. SQL schema

Explain why each table exists. 
Keep the database simple enough for a beginner hackathon team to understand and maintain.
Do not include AI-specific tables like Embeddings or PromptLogs.

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