Boundaries included in Spatial Join

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03-27-2018 03:37 PM
LindseyWinn
New Contributor III

Hello! I'm trying to perform a spatial join (one to many). for the "places" city shapefile and the US counties shapefile. I want to see all of the counties the places shapefiles overlap, but because some of the places share a boundary with the counties, it includes those counties as well (something I'm trying to avoid). How do I omit those counties that only share a border with a place shapefile? I considered converting polygons to points, but then I wouldn't get all of the counties if some place shapefiles overlap. Does this make sense? Thank you!

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7 Replies
DanPatterson_Retired
MVP Emeritus

You should really look at this link, since it has visual representations of the various options arranged by the geometry type.  Examine the options available including the 'clementini' variants with respect to your geometry.

When this diagram is on hand, you will see whether there is a need or not to convert one or both of the geometry types.  In the vast majority of situations, there is not.

A good link to have on hand... Select by Location: Graphic Examples

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LindseyWinn
New Contributor III

It does look like Within Clementini is what I need to be using, but it doesn't seem to give a "one to many" output for those city polygons that overlap more than one county. Does this function allow for a one to many output? 

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DanPatterson_Retired
MVP Emeritus

Lindsey, for that just go back to the Spatial Join help topic and examine the input parameters in detail

AbdullahAnter
Occasional Contributor III

Could you draw a picture for what exactly you want to do?

LindseyWinn
New Contributor III

See image. I'm trying to perform a spatial join (one to many). for the "places" city shapefile (blue polygons) and the US counties shapefile (pink polygons with red outlines). I want a list of all of my cities (blue polygons) and the counties they overlap. The problem I run into is the type of polygon on the left side of the image. It's exactly the same shape as the underlying polygon, so when I join the two together, it returns all of the surrounding counties (when I really just want the underlying county). I'm trying to use Clementini for a one to many join (because like the polygon on the right, it overlaps two counties), but the results don't give me a one to many, just one county per city polygon. 

Does this help?

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GISLearner
New Contributor III

I'm struggling with this exact issue, were you able to find a solution?

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GISLearner
New Contributor III

Found a smart solution here for anyone running into this problem who comes across this question: https://gis.stackexchange.com/questions/216931/using-select-by-location-intersect-how-to-exclude-the...