Currently, when using the Spatial Join geoprocessing tool, there is only one match option for matching centroids of features, which is "Have their Center In". The opposite is needed for when joining many small polygons to fewer larger polygons that they are within the large polygons. This could be called "Contains the center point of."
Scenario:
Target features are districts, and join features are properties within those districts. We'd like to do a spatial join to roll up statistics from the parcels into the districts. The "Have their center in" match option won't work because it will only join items where the centroid of the district is inside the smaller parcel. Intersects won't work because if there are parcels around the district boundary that slightly touch the district, they will be counted in the statistics when they shouldn't be. Contains and completely contains won't work because parcels that are partially within the district but have portions outside won't be counted.
In this case, a new match option "Contains the center point of" could accomplish this goal. Currently a workaround requires doing a Feature to Point geoprocessing tool on the parcel polygon first, creating a centroids feature class, and then doing a spatial join with the parcel centroid points as the join featureclass, and the districts as the target featureclass, with the match option set to "Contains." This accomplishes the goal, but requires two steps and isn't intuitive to users.
We have the same need! Our workaround was to spatially join the larger polygons to the smaller polygons in a one-to-one join using the "have their center in" match option and then dissolving the resulting output layer on the unique ID of the join layer (larger polygons), aggregating the fields we needed. Then we could do a regular join to join the fields from the dissolved layer to the larger polygons on their unique ID. But this is such a common task (aggregating sub-areas to a larger containing polygon where outer boundaries are shared or may not match perfectly) that there should be a match option allowing us to simply match and join the smaller polygons to the target polygon that they are mostly in. This suggestion would take care of that.
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