# Database Design

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- Skill: `anhvu1107/database-design` (Agent Skill, multi-file: 15 files)
- Install (CLI): `npx skillmds@latest add anhvu1107/database-design`
- Raw SKILL.md: https://api.skillmd.com/api/skills/anhvu1107/database-design/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: anhvu1107 (https://skillmd.com/u/anhvu1107)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/anhvu1107/database-design

---

---
name: database-design
description: ALWAYS use this when the hard part is schemas, relationships, constraints, indexes, data integrity, query shape, or migration-safe data modeling.
---

# Database Design

## Selective Reading Rule

Start with:

- `references/usage-routing.md`
- `references/quality-checklist.md`

Then load only the inherited docs, scripts, assets, or examples that match the user's actual task.

> **Learn to THINK, not copy SQL patterns.**

## Supplementary References

Start with:

- `references/senior-master-standard.md`
- `references/schema-routing.md`
- `references/migration-safety.md`

Then load only the root markdown files that match the actual database question.

## đŸŽ¯ Selective Reading Rule

**Read ONLY files relevant to the request!** Check the content map, find what you need.

| File | Description | When to Read |
|------|-------------|--------------|
| `database-selection.md` | PostgreSQL vs Neon vs Turso vs SQLite | Choosing database |
| `orm-selection.md` | Drizzle vs Prisma vs Kysely | Choosing ORM |
| `schema-design.md` | Normalization, PKs, relationships | Designing schema |
| `indexing.md` | Index types, composite indexes | Performance tuning |
| `optimization.md` | N+1, EXPLAIN ANALYZE | Query optimization |
| `migrations.md` | Safe migrations, serverless DBs | Schema changes |

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## ⚠️ Core Principle

- ASK user for database preferences when unclear
- Choose database/ORM based on CONTEXT
- Don't default to PostgreSQL for everything

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## Decision Checklist

Before designing schema:

- [ ] Asked user about database preference?
- [ ] Chosen database for THIS context?
- [ ] Considered deployment environment?
- [ ] Planned index strategy?
- [ ] Defined relationship types?

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## Anti-Patterns

❌ Default to PostgreSQL for simple apps (SQLite may suffice)
❌ Skip indexing
❌ Use SELECT * in production
❌ Store JSON when structured data is better
❌ Ignore N+1 queries