Database Schema Design

Handles the fundamentals of relational database design with a focus on normalization forms and relationship patterns. You'll use this when you're designing schemas from scratch or refactoring existing ones that have grown messy. It walks through 1NF, 2NF, and 3NF with concrete examples of eliminating repeating groups, partial dependencies, and transitive dependencies. Covers both PostgreSQL and MySQL. The approach is straightforward and example-driven, showing you the wrong way and the right way side by side. Honestly, if you already know your normal forms well, this is basic, but it's solid for getting teams on the same page about schema design principles.

skills.sh installs: 597
GitHub stars: 379
last updated: Aug 21, 2026

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Install

$ npx -y skills add aj-geddes/useful-ai-prompts --skill database-schema-design --agent claude-code

Installs into .claude/skills of the current project.

Files

Overview

Design scalable, normalized database schemas with proper relationships, constraints, and data types. Includes normalization techniques, relationship patterns, and constraint strategies.

When to Use

New database schema design
Data model planning
Table structure definition
Relationship design (1:1, 1:N, N:N)
Normalization analysis
Constraint and trigger planning
Performance optimization at schema level

Quick Start

PostgreSQL - Eliminate Repeating Groups:

-- NOT 1NF: repeating group in single column
CREATE TABLE orders_bad (
  id UUID PRIMARY KEY,
  customer_name VARCHAR(255),
  product_ids VARCHAR(255)  -- "1,2,3" - repeating group
);

-- 1NF: separate table for repeating data
CREATE TABLE orders (
  id UUID PRIMARY KEY,
  customer_name VARCHAR(255),
  created_at TIMESTAMP DEFAULT NOW()
);

SKILL.md on GitHub