0

I have a raster table in PostGIS. When I run ST_SetValue(rast, geom , value) on it to change the pixel value at a point, it works very slowly. Do you know how can I create spatial index for a raster column? (I could not create it using PgAdmin interface with gist method)

3
  • 1
    Did you tile your raster? It makes a big difference to pixel access speeds and spatial search in general. – John Powell Jul 12 '19 at 16:36
  • 1
    Usually, for rasters, you tile the bounding box of each tile, even though mutliple tiles constitute a complete coverage. Obviously, indexing each pixel is pointless and indexing the bounding box of the raster is pointless, but indexing each sub-tile of the raster will make this a lot quicker, as you have to open much fewer points before you can run ST_SetValue. See this answer, for example. – John Powell Jul 15 '19 at 11:21
  • or this one: gis.stackexchange.com/questions/43053/… – John Powell Jul 15 '19 at 11:25
1

So when you are using raster2pgsql raster_options_go_here raster_file someschema.sometable > out.sql, use -I tag, that will create a GiST index on the raster column.

For more go here here

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.