Most .NET developers have worked with dates, strings, and decimal columns their entire careers — but the moment someone asks "show me all the customers within 30 miles," the usual LINQ query falls short. Spatial data isn't exotic; it's just a data type most of us were never taught to use. And once you know how, it unlocks queries, analyses, and visualizations that are impossible any other way.

This session walks the full path from database to dashboard. We'll start in the schema — defining geometry and geography columns in SQL Server and PostgreSQL, mapping them through EF Core with NetTopologySuite, and writing spatial queries (intersections, distance calculations, containment checks) that run on the database, not in memory. From there, we'll serialize results as GeoJSON, feed them into a Blazor front end, and render them as interactive map layers users can explore. Along the way, you'll see how spatial indexes actually work, when to choose `geography` vs. `geometry`, and how to avoid the performance traps that catch most first-timers.

No GIS background needed — just a willingness to think of your data as shapes on a map instead of rows in a grid.