[postgis-users] bounday or convex hull of a bunch of points

[Paul Tomblin]

I have a table with a point column.  Is there a way to find the boundary or 
convex hull of some of the entries in that table?  For instance, if I want to 
find the extents of each country in the table, can I say
	insert into country_extents (country, geom) values (select country, 
ST_XXX(point) from waypoint group by country));

-- 
Paul Tomblin <ptomblin at xcski.com> http://blog.xcski.com/
"I'm cruising down the Information Superhighway in high gear, surfing the
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