jiayuasu opened a new issue, #3176:
URL: https://github.com/apache/sedona/issues/3176

   ## What's missing
   
   Neither `ST_ConvexHull` nor the aggregate that feeds it (`ST_Collect` / 
`ST_Collect_Agg` /
   `ST_Union_Agg`) accepts geography, so a grouped hull cannot be computed on 
the sphere.
   
   ```sql
   -- wanted
   SELECT ST_Area(ST_ConvexHull(ST_Collect(ARRAY_AGG(geog)))) FROM ... GROUP BY 
...;  -- m^2
   ```
   
   ## Why
   
   Together these block the geography form of SpatialBench Q5, which takes the 
convex hull of
   each customer's monthly dropoff locations and reports its area. Under 
geography the hull is
   built from geodesic edges and the area is in m², so the number means 
something; the planar
   version reports square degrees.
   
   ## Reference
   
   SedonaDB implements `ST_ConvexHull(geography) -> geography`, and its 
`ST_Collect_Agg` accepts
   geography as well (undocumented there — apache/sedona-db#1087), so the 
combination works
   end to end today and can serve as a reference.
   
   Part of https://github.com/apache/sedona/issues/2830.
   


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