QueryCity Academy
An interactive 3D database classroom where students run real SQL queries and watch the planner, executor, and buffer cache light up like a working city - the educational version of PGSimCity.
computer science undergraduates and bootcamp students learning database internals
- Plug-and-play PostgreSQL sandbox with visual query lifecycle (parse, plan, execute, fetch)
- 'Slow query lab' that lets students toggle indexes, batching, and vacuum settings to see runtime drop
- Lesson packs tied to standard undergraduate DB curricula (Ramakrishnan, Silberschatz)
- Recordable tour mode that exports the 3D walkthrough as a teaching video
PGSimCity's 355-point HN hit proves developers and educators actively want a visual model of how Postgres works, yet most online DB courses still teach through static diagrams
PGSimCity hit #1 on HN and sparked multiple clone projects (Database Internals Visualizer, SQL Execution Visualizer, SQLVis), confirming real educator/dev interest — but that interest is already being absorbed by several free tools.PGSimCity - How PostgreSQL Works | Hacker News ↗Database Internals Visualizer ↗
Crowded fast: PGSimCity itself plus Database Internals Visualizer, SQL Execution Visualizer, Schema3D, SQLVis, and Datadog's Explain Plan Visualizer all target the same visual query-internals niche within months.SQL Execution Visualizer — Interactive B+Tree & Query Engine ↗Schema3D: 3D Database Schema Visualizer for SQL & Mermaid ↗SQLVis — Interactive SQL Learning Platform ↗
Codecademy/DataCamp prove students pay $25+/mo for SQL courses and Markus Winand sells SQL performance training/books, so WTP exists — but most standalone visualizers (PGSimCity, Schema3D, Datadog's explain tool) ship free, capping premium pricing.Pricing | Codecademy ↗Plans and Pricing - Choose a Package | DataCamp ↗Online SQL Training with Markus Winand ↗
Database internals are taught in every CS curriculum indefinitely, but PGSimCity is already flagged as 'early prototype' and similar projects appear and stall — long-term value depends on continuous content updates.GitHub - NikolayS/PGSimCity ↗
Multiple solo developers have shipped working WebGL/JS query visualizers (PGSimCity on WebGL2, SQL Execution Visualizer on Vercel), proving the core tech is buildable by a small team in months.PGSimCity - How PostgreSQL Works - daily.dev ↗SQL Execution Visualizer — Interactive B+Tree & Query Engine ↗