I have a number of nodes selected.
I now want to select all subcatchments that go to this nodes. And than add all the numbers of the field "population" of the selected subcatchments.
Then I want to fill in this addition to the fiels "usernumber1" of this node.

I think I'll need :
SET us_subcatchments.$node_selected = 1 where $Node_selected = 1

But "us_subcatchments" doesn't exist in this SQL ?

Can someone help me with this ?