The business problem
Planet Fitness wants a single database to power club operations across hundreds of locations: who's a member, what membership tier, which class are they in, which trainer, who paid, who didn't. The functional spec describes the business; your job is to translate it into a normalized schema, defend the design, and write the queries operations needs.
This case is the canonical end-to-end Database Design Document (DDD) exercise — the same structure you'll be expected to produce in industry on day one.
Case kit
The brief — start here
- Functional SpecificationThe "before" — what the business is asking for. Read first.
- DDD — Student TemplateThe deliverable template. Fill it in as you design.
Reference design (try yours first!)
Compare against the reference solution after you've drafted your own.
- DDD — Reference Solution
- Planet_Fitness_Database_v1.1.sqlReference SQL schema — the working version of the design.
- planet_fitness_database.sqlEarlier flavor for comparison.
Query the schema
- SQL Practice Worksheet (Student)Business questions to answer with SQL once the schema is up.
- SQL Solution GuideSample solutions — try yours first.
Topics you'll be applying
- Decision 3 — Database Design · the core technique
- Decision 4 — Business Rules · constraints & integrity
- Decision 2 — Querying · the SQL practice phase