The Desi Architect
Notes / Docker Sandboxes / Spatial Proximity & Dispatch: Redis GEO vs PostgreSQL PostGIS
Docker Sandboxes · Tier 2: Data & Scale · Lab 67

Spatial Proximity & Dispatch: Redis GEO vs PostgreSQL PostGIS

Dispatch nearby delivery partners within 2 kilometers across Bengaluru. Compare Redis GEO in-memory Geohash sorted sets with PostgreSQL PostGIS GiST spatial indexing, prove boundary accuracy with a strict exclusion band, audit execution plans, and measure the MVCC dead tuple churn of rapid driver GPS updates.

Time35 minutes
StackPostGIS 3.4Ports 16425, 15456
MemoryAbout 150 MB
Before thisLab 04SQL Basics with PostgreSQL
Download lab (.zip) View steps
Verified runWindows, Mac, LinuxBash and PowerShell
  1. 1PrepareWhat you will learn
  2. 2PredictGuess before you run
  3. 3RunStep by step
  4. 4ObserveWhat you should see
  5. 5Break itChange one thing
  6. 6Clean upLeave nothing running
On this page
  1. 00 / What You Will Learn
  2. 01 / Why It Matters
  3. 02 / What We Are Building
  4. 03 / Words You Need
  5. 04 / Predict First
  6. 05 / Step by Step
  7. 06 / What You Should See
  8. 07 / Look Inside
  9. 08 / Break It, Fix It
  10. 09 / In Real Projects
  11. 10 / Interview Corner
  12. 11 / Clean Up

00 /What You Will Learn

By the end you will be able to
  • Explain how Redis GEO encodes coordinates into 52-bit integer Geohashes in a Sorted Set.
  • Run spatial proximity dispatch queries using PostGIS ST_DWithin and Redis GEOSEARCH.
  • Audit query execution plans with EXPLAIN to verify GiST spatial index scans versus sequential scans.
  • Design deterministic spatial test suites using a boundary exclusion band.
  • Measure the database storage impact of high-frequency GPS coordinate update churn.

Before you start

Complete Lab 04 (SQL Basics with PostgreSQL) and Lab 06 (Redis Basics) first. You should know how to run SQL queries and interact with Redis keys. Docker Desktop must be running.