Hello, I've got a question about using ST_Collect.
I have one table with hundrets of thousands of points. Within this table I want to collect the points that are within a 500 meter radius and calculate a convex hull around them. Since the ST_DWithin needs (geom, geom, distance) and I only have one table with points, do I first have to perform a self join to identify the points within 500 meters and then a ST_Collect to group these points? Or can I somehow do it without joining the one table with itself? And can I use the ST_DWithin inside the ST_Collect? Like ST_Collect(ST_DWithing(geom,geom,distance))? Thanks for your help! -- Carsten
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