database-design
Installation
SKILL.md
Database Design
Design efficient, scalable database schemas.
Normalization
| Normal Form | Rule | Violation Example |
|---|---|---|
| 1NF | Atomic columns, no repeating groups | phone_numbers: "555-0100,555-0200" |
| 2NF | 1NF + all non-key cols depend on full PK | Orders table with product details |
| 3NF | 2NF + no transitive dependencies | Employee with department_name (dept info in dept table) |
When to denormalize: Read-heavy workloads, reporting, caching layers.