Diagnose and Fix Query-Planner Misestimates in a FinTech Warehouse
Overview
What this challenge is about.
You diagnose and fix 6 query-plan misestimates in a FinTech warehouse, then validate no regression. Earn a verifiable certificate.
The scenario
The FinTech (regulated under FCA (UK Financial Conduct Authority)) cannot miss nightly reporting SLAs — they feed customer balances and regulatory reports.
The Brief
What you'll do, and what you'll demonstrate.
Diagnose 6 planner-misestimate-driven slow queries on a 4.2 TB PostgreSQL warehouse, fix them, and write a tuning playbook the team can reuse.
Earning criteria — what you'll demonstrate
- Read EXPLAIN (ANALYZE, BUFFERS) deeply enough to spot misestimates
- Apply CREATE STATISTICS to correlated and dependent columns
- Validate fixes against non-target queries to prevent regression
- Write a tuning playbook that lasts beyond the immediate fix
Program Fit
Where this fits in your program.
Sharpens the same skills your degree expects you to demonstrate.
Advanced Database Systems
Master · Databases
Strong alignment
This challenge maps to Advanced Database Systems at the Master level. It sharpens the same practical skills your coursework expects — but in a real industry context with actual constraints and deliverables.
Skills
Skills you'll demonstrate.
Each one shows up on your verified credential.
- Query Optimization
Apply query optimization to solve real industry problems and demonstrate production-level capability.
- Postgresql Planner
Apply postgresql planner to solve real industry problems and demonstrate production-level capability.
- Extended Statistics
Apply extended statistics to solve real industry problems and demonstrate production-level capability.
- Explain Analyze
Apply explain analyze to solve real industry problems and demonstrate production-level capability.
- Performance Tuning
Apply performance tuning to solve real industry problems and demonstrate production-level capability.
- Regression Testing
Apply regression testing to solve real industry problems and demonstrate production-level capability.
Careers
Career paths this challenge builds toward
Completing this challenge demonstrates skills that transfer directly to these roles: