I have a simple SpatiaLite DB containing one table with point features. I would like to generate a Minimum Convex Hull around that features. I could do that easily with one of the Convex Hull tools from GDAL/SAGA/GRASS/R-Script... from processing toolbox. But I would like to have a dynamic SQL solution. So every time a new point feature is added, the Convex Hull should automatically be updated. So I thought about a SQL-View:
I tried around following this instructions: http://postgis.net/docs/ST_ConvexHull.html
CREATE VIEW birdsmcp AS SELECT ST_ConvexHull(ST_Collect(geom)) FROM birds GROUP BY bird;
I get a table, but no geometry. What do I have to do to get shapes as a result? I'm not very familiar with SQL queries.