Schema design for real products

Data modeling practice

Data modeling is how builders represent a product domain so the system can answer questions, enforce rules, and evolve without collapsing. AI can generate tables, but product-minded engineers know which entities matter, which access patterns dominate, and where denormalization is worth it.

Who should practice data modeling?

Backend engineersData engineersAnalytics engineersPMs working with data-heavy products
Outcomes

What Hatch trains you to do

These are the capabilities the app grades and coaches while you work through scenarios.

Identify core entities
Model relationships and constraints
Design event taxonomies
Optimize for access patterns
FLOW mapping

How FLOW scores data modeling

The same four moves apply across every discipline, but the evidence changes by track.

Frame

Frame the product domain, actors, rules, and access patterns.

List

List entities, relationships, events, and invariants.

Optimize

Optimize normalization, denormalization, history, and tenant boundaries.

Win

Win by explaining how the model answers future product questions.

Practice formats

Representative prompts

Multi-tenant SaaSBilling and meteringAudit logsMarketplace entitiesEvent tracking plans
Model a multi-tenant SaaS product with billing, usage metering, and audit logs.
Design the event taxonomy for an AI assistant product.
Model listings, bookings, payments, and disputes for a marketplace.
FAQ

Questions about data modeling

Is data modeling different from SQL?

Yes. SQL asks how to retrieve or transform data. Data modeling asks what data should exist, how it relates, and which constraints the system should enforce.

Why does data modeling matter for product sense?

A strong data model determines which product questions can be answered later: retention, monetization, fraud, usage, and customer health.

Turn data modeling into reps.

Public previews show the map. The app gives you reps, Hatch follow-ups, FLOW feedback, weak-move drills, and saved proof of progress.

Start a free rep