database-design | SkillBundle

Database Design

Learn to THINK, not copy SQL patterns.

🎯 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

⚠️ Core Principle

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

Decision Checklist

Before designing schema:

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

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

Database Design

Learn to THINK, not copy SQL patterns.

🎯 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

⚠️ Core Principle

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

Decision Checklist

Before designing schema:

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

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