Export DVF geolocalisées en Geoparquet

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Export DVF geolocalisées en Geoparquet

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Last edited May 18, 2026

Created on May 18, 2026

This example converts French land-registry transaction data (DVF) from compressed CSV files into a single spatially-indexed GeoParquet file. It downloads yearly datasets from data.gouv.fr, loads them into a DuckDB database, and creates a point geometry for each transaction before exporting with a Hilbert-curve spatial ordering. The script leverages DuckDB’s spatial extension, the `ST_Point` and `ST_Hilbert` functions, and parquet compression via zstd.

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