Expose geometry type as an arrow geometry format

[Skaidus]

First of all great work with this extension!

I've tried to query geoparquet files using duckdb and its geospatial extension. It seems that it has its own binary type for performance. I would like to know about how would it be mapped directy to geoarrow, since converting it to WKB or WKT as an intermediate step makes the performance gains probably not worth it.

In addition, would love to know more about the geometry type internals.

Thank you in advance.

[Maxxen]

Hello!
DuckDB v1.5 will map geometry columns to to GeoArrow WKB when exporting through arrow automatically.
Converting to WKB is generally very cheap - we're talking like milliseconds for multiple millions of rows.
The internal format is intentionally not documented as we are still making changes to it, so you should always use some conversion function (ST_AsWKB/ST_GeomFromWKB/ST_AsGeoJSON/ST_AsWKT etc.) to export/import. We still have some things we want to test out, but hopefully we can make a decision and document it for v1.6.