Assistance in QGIS operations

[Aleksandr]

Good evening, I need to calculate (combine the attribute table) in QGIS in two layers, both polygons (one polygon of buildings, the other polygon of neighborhoods). I need the population of buildings in the same neighborhood to be summed up and displayed (in a new layer or in the layer with neighborhoods) as a whole. The final goal is to create a layer with neighborhoods and their population in the database.

 

[Forgotten_Wealth6]

Search for the tool called "Join Attributes by Location (Summary)". Set your neighborhoods layer as the input layer and the buildings layer as the join layer. For the fields to summarize chose your population column and select 'sum' for the summary calculation. The output will be a new neighborhoods layer with a field containing the total population count.

 

[Carbguy]

You can do that with a Spatial Join in QGIS, join buildings to neighborhoods, then use the group stats or aggregate function to sum the population field by neighborhood. That'll give you a new neighborhood layer with total population values.