Database Schema Design Skill

Produce a complete database schema design document for a given domain. A schema document is not just a list of tables — it is a record of decisions: what was modelled, how entities relate, which queries the schema is optimised for, and what trade-offs were made.

A good schema design document lets an engineer understand the data model, query it correctly, extend it safely, and write migrations without breaking things.

Required Inputs

Ask for these if not already provided:

• Domain description — what the system does; what business objects are being modelled
• Entities and relationships — the main things in the domain and how they relate (e.g. "a User has many Orders; an Order has many OrderItems; an OrderItem references a Product")
• Expected query patterns — the most important read and write queries (e.g. "fetch all orders for a user, sorted by date"; "look up a product by SKU")
• Database engine — PostgreSQL, MySQL, SQLite, CockroachDB, etc. — this affects DDL syntax and available types
• Expected data volume — approximate row counts, growth rate, and any partitioning needs
• Constraints — any existing conventions, naming standards, or migration constraints to respect

Output Format