I am having 15 polygon shape files of a sub locality of a city that is having address in their attribute table. I want to merge these polygons based on the address in the attribute table?how can i do this in Qgis. I also attempted vector...>>>data management tools...>>>>merge shape files to one.But it is giving me the combined polygon but when I look into the attribute table the values shows me null? What is the problem behind it?
QGis's fTool's dissolve
tool did not work for me, so I'm solving this on rails :)
Now this solution might not be good for some, because you have to load in every parcel into a database, but I had already done that so it worked for me.
Here's my pseudo code, I haven't run anything yet
Polygon.all.each do |p|
if check_if_superpolygon_exists(p)
if check_if_contiguous_superpolygon_exists(p)
add_to_contiguous_superpolygon(p)
else
create_new_superpolygon(p)
end
else
create_new_superpolygon(p)
end
end
check_if_contiguous_superpolygon_exists
will use ST_Intersects & the others will just check if records exist with the same attribute-value and stuff. The only tricky part I haven't done yet is merging a new polygon into the superpolygon's spatial data.