Combining information of two layers in one

Question

I'm working on population data by catchment area in Albania.

I'd like to know how many people are living inside one precise catchment area and in every catchment area.

For example in the first picture, I have my polygons, containing points for population areas.

I used the intersection tool to make intersect pop data and catchment area, but it only gives me the data of catchment areas, without population in it (see picture 2).

Is there a way to combine the catchment area with those points so that when I click on one catchment I have all the dots inside with population data?

Answer 1

You can use Join attributes by location tool to join point data with the catchment polygon using Intersects as geometric predicates:

• Target vector layer: Population points
• Join vector layer: Catchment polygon
• Geometric predicates: Intersects
• Run the tool

You need to make sure the coordinates of both vector layers are same.