[postgis-users] Help with SQL

[paul.malm at lfv.se]

Hi,
I have 2 tables:
obstacles (point layer) with a column height_m (INTEGER) and a
polyobstacles (polygon layer)
the point layer has obstacles all over the map and the polygon layer has some polygons containing some of the obstacle points.
Now I would like to select the highest obstacle in each polygon. If there is several points with the same highest height a random obstacle of those highest shall be selected.
Is there someone that can get me on the track for such a query, I'm losing myself in subqueries?
Kind regards,
Paul


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   Paul Malm

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