I have two shapefiles. One is the DMA and another of states.

What I'm trying to do is "expand" a DMA boundary to match the boundary of the states, since the DMA map doesn't extend all the way. To illustrate:

This is the map of the Mid Atlantic and Midwest region states:


And this is the DMA for the same region: dma

And this is the overlay between the two shapefiles: overlay

Is there any way I can create a query that will artifically increase the size of the DMA to match the state boundaries? The reason why I need this is because I plan on going a large spatial join with coordinates and I know alot of people will not be counted for if we use the current DMA shapefile.

1 Answer 1


I saw on you page that you converted a shapefile to topojson. Try getting the original DMA shapefile and projecting it so that it matches the state shapefile. I looks like a projection error. Also, the DMA doesn't match up with state boundaries, so a join might give you fits. You could do something like a spatial join or clip.


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