SQL query: insert values into polygon where features of the polygon intersects another polygon
You're not allowed to reference table_A in the insert inside the select. The query needs to work stand-alone.
The following should work (untested):
insert into schema.table_A(columnKJ1)
select &quot;columnPO4&quot;
from schema.table_B
join schema.table_A on st_intersects(table_a.geom, table_B.geom);