Only selecting Features that have another layers feature on top

Question

So I am busy with a aerial fibre plan and have Splitters on certain poles (these layers overlap each other). There are over 3000 poles and only 1699 of those poles that have a splitter on them.

Is there any way I can just select the poles that have splitters on to use these attributes on my splitter layer attributes?

I've tried to do this manually but there's too much room for error

Answer 1

You can use Select By Expression CTRL+F3:

overlay_nearest(
   layer:='Splitter',
   limit:=1,
   max_distance:=5)

on your Poles layer. Replace Splitter with the name of your splitter layer.

The expression is searching for any splitter feature within a distance of 5 (adjust this value, the units are the units of your CRS, in my case meters) and returns True if there is one.

The reason for using overlay_nearest and a distance instead of overlay_intersects is that sometimes two points that looks like they are on top of each other actually are not, but off by a very small distance.

Answer 2

Another option - use the field calculator to access the field in the poles layer that you want to transfer to the splitter layer with an expression like this:

This expression will set the new field in the splitters layer which is called pole_id to the nearest pole's value for random_id from the poles layer. Note that the layer name is case sensitive.

array_first
    (overlay_nearest
        (layer:='Poles',
         expression:="random_id",
         max_distance:=1
        )
    )

Result: