paleolimbot commented on issue #686:
URL: https://github.com/apache/sedona-db/issues/686#issuecomment-4000908277

   This one is from the release post: deduplicating buildings from a large ish 
Parquet file. I think DuckDB is faster at this one because of its hash join but 
I'm not sure.
   
   ```python
   # pip install "apache-sedona[db]" --force-reinstall --pre 
--extra-index-url=https://pypi.fury.io/sedona-nightlies/
   # curl -L 
https://github.com/geoarrow/geoarrow-data/releases/download/v0.2.0/microsoft-buildings_point.parquet
 -o buildings.parquet
   import sedona.db
   
   sd = sedona.db.connect()
   sd.options.memory_limit = 'unlimited'
   
   url = "buildings.parquet"
   sd.read_parquet(url).to_view("buildings")
   sd.sql(
       """
       SELECT ROW_NUMBER() OVER () AS building_id, geometry
       FROM buildings
       """
   ).to_parquet("buildings_idx.parquet")
   
   sd.sql(
       """
       SELECT
           l.building_id,
           r.building_id AS nearest_building_id,
           l.geometry AS geometry,
           ST_Distance(l.geometry, r.geometry) AS dist
       FROM "buildings_idx.parquet" AS l
       JOIN "buildings_idx.parquet" AS r
           ON l.building_id <> r.building_id
           AND ST_DWithin(l.geometry, r.geometry, 1e-10)
       """
   ).to_memtable().to_view("duplicates", overwrite=True)
   
   # 30.8s
   sd.view("duplicates").count()
   #> 1017476
   
   # pip install --force-reinstall --pre duckdb
   import duckdb
   
   duckdb.load_extension("spatial")
   
   # 19s
   df = duckdb.sql("""
       SELECT
           l.building_id,
           r.building_id AS nearest_building_id,
           l.geometry AS geometry,
           ST_Distance(l.geometry, r.geometry) AS dist
       FROM "buildings_idx.parquet" AS l
       JOIN "buildings_idx.parquet" AS r
           ON l.building_id <> r.building_id
           AND ST_DWithin(l.geometry, r.geometry, 1e-10)
       """)
   len(df)
   #> 1017476
   ```


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