docs: crs tracking example

[MrPowers]

I'm trying to demonstrate how SedonaDB tracks CRSs and doesn't allow for operations with mismatched CRSs.

Doesn't look like this code is properly setting the CRS:

cities = sd.sql("""
SELECT * FROM (VALUES
    ('New York', ST_SetSRID(ST_GeomFromText('POINT(-8238310.24 4969803.34)'), 3857)),
    ('Los Angeles', ST_SetSRID(ST_GeomFromText('POINT(-13153204.78 4037636.04)'), 3857)),
    ('Chicago', ST_SetSRID(ST_GeomFromText('POINT(-9757148.04 5138517.44)'), 3857)))
AS t(city, geometry)""")

cities.schema
SedonaSchema with 2 fields:
  city: Utf8
  geometry: Binary

Let me know if you have any suggestions on how to fix the code!

[paleolimbot]

Let me know if you have any suggestions on how to fix the code!

I believe this is caused by a DataFusion bug (all extension information in a VALUES clause are dropped). You should be able to work around this by moving the function call to the SELECT (also shorter!).

cities = sd.sql("""
SELECT city, ST_SetSRID(ST_GeomFromText(wkt), 3857) AS geometry FROM (VALUES
    ('New York', 'POINT(-8238310.24 4969803.34)'),
    ('Los Angeles', 'POINT(-13153204.78 4037636.04)'),
    ('Chicago', POINT(-9757148.04 5138517.44)'))
AS t(city, wkt)""")