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I need to develop a process for merging the attributes of each point in a SDE feature class with a polygon in a SDE feature class that contains the point to create a third feature class. The third feature class should contain the attributes of the point with the geometry of the polygon. This seems to be a spatial join. Is that assumption correct?

The points represent incident locations. The polygons represent counties. The team is requesting I intersect the incident with the county to create the third feature class. There will be multiple incidents per county so they expect to see a row for each incident and the county geometry will be repeated.

I've been using ArcToolbox > Analysis Tools > Overlay > Spatial Join. Setting the Target Feature to the incidents layer and the Join Features to the counties layer yields the correct number of rows but the geometry is a point. I need a polygon. Switching the Target Feature and Join Features yields the correct geometry but not the correct number of rows.

How should I be approaching this?

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    Have you tried using the switched target and join features (so your output is polygon) but set the join operation as "JOIN_ONE_TO_MANY"? – Ali Oct 2 '15 at 15:24
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    @Ali would you mind giving that as an answer? as long as multiple polygons are not a problem, this should work just fine. – yanes Oct 2 '15 at 16:13
  • I would suggest thinking a bit more about the problem. Do you really want a third dataset in which polygon geometries are repeated? Why not just add a foreign key between the incidents and the counties they are in? This is not a difficult procedure, so what happens when new incidents are added or the county boundaries are changed? Why can't an incident's county be requested when it needed rather than the procedure you have outlined, which leads to redundancy in your data? – Richard Law Oct 3 '15 at 19:30
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You are quite correct to approach this using a Spatial Join. However, it looks like you want to specify the Join Operation parameter as "JOIN_ONE_TO_MANY" since you have many incidents inside each county.

Your output will then contain one Target Feature for each Join Feature that meets the criteria for your Match Operation. That is, for each incident, a corresponding county polygon feature will be generated and contain the attributes of the county AND the incident within it.

From my understanding of your explanation, this should satisfy your requirements.

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Although, as commented, a point-in-polygon overlay like this can be performed using the multi-purpose Spatial Join tool, I would recommend also being aware of the Intersect tool that has a much simpler interface:

Computes a geometric intersection of the input features. Features or portions of features which overlap in all layers and/or feature classes will be written to the output feature class.

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Attribute values from the input feature classes will be copied to the output feature class.

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