Query remote Geoparquet in browser

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Query remote Geoparquet in browser

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Last edited Dec 1, 2025

Created on Dec 1, 2025

This example demonstrates querying a remote GeoParquet file directly from a web browser using DuckDB-Wasm. The interactive map displays French priority neighborhoods (QPVs) and identifies which one contains a specific geographic point (2.389798, 48.909514). It uses DuckDB-Wasm’s SQL engine with the spatial extension to run an `ST_contains` query, filtering results by geometric intersection. The workflow converts the matched polygons to GeoJSON via the GDAL driver and exports them as a downloadable file. The dataset was prepared from a government GeoJSON source using DuckDB and gpio utilities.

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