Spatial SQL: Geo-spatial Analysis in the Browser (2026)

In the past, if you wanted to find every dealership within a 10-mile radius of a user's coordinate, you'd hit a PostGIS backend. In 2026, that architecture is considered legacy for high-performance applications.

With the maturity of DuckDB-Wasm and the GeoArrow standard, we can now run complex spatial analysis directly in the user's browser thread.

Why Client-Side Spatial SQL?

1. 2.
   Instant Feedback: Map interactions are no longer blocked by network round-trips.
2. 4.
   Privacy: User locations and query parameters stay on the device.
3. 6.
   Reduced Server Costs: Move the heavy lifting to the client's high-performance hardware.

Setting Up DuckDB-Wasm for Spatial

DuckDB-Wasm recently added first-class support for the spatial extension.

```javascript import * as duckdb from '@duckdb/duckdb-wasm';

const db = new duckdb.AsyncDuckDB(logger, worker); await db.instantiate(main_wasm, network_wasm);

const conn = await db.connect(); await conn.query("INSTALL spatial; LOAD spatial;"); ```

Querying GeoJSON Data

Once the spatial extension is loaded, we can treat GeoJSON or Parquet files as relational tables.

```sql SELECT name, ST_Distance( ST_Point(lon, lat), ST_Point(-73.935242, 40.730610) ) AS distance FROM 'points.parquet' WHERE distance < 10000 ORDER BY distance ASC; ```

Conclusion

The browser is no longer just a rendering engine; it's a data warehouse. Spatial SQL is just the beginning of a shift where the "Frontend" handles the logic that used to live exclusively in the "Database."