Increase cost of ST_ConvexHull(raster)
|Reported by:||strk||Owned by:||strk|
The cost of ST_ConvexHull(raster) is currently set to 1. For comparison ST_ConvexHull(geometry) is 100, and st_intersects(raster, raster) is 1000.
Real world cases have been found where a cost of 100 is not enough for the planner to choose a functional index scan for a query using a spatial condition on the raster column, while such index scan would take half the time (probably due to the pre-computation of the function output). See http://lists.osgeo.org/pipermail/postgis-devel/2014-August/024461.html
Raising it to 200 seems enough for the specific case.
It's to be determined out to deal with upgrades on function cost changes.
See #2839 for the change that made the problem more evident.