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How To: Spatially join one point to multiple polygons

Summary

Joins are set up on a 1 to 1 basis. The only way to join 1 to many or many to many is to do a relate. Relates cannot be preformed spatially. They have to be done through the attribute table. This document contains information on how to spatially join one point to multiple polygons.

Note:
If a point feature that falls within two polygon features, then the output of the spatial join will be that the point feature is joined with the polygon feature with the lowest ObjectID.

Procedure

There are two processes that can be tried in order to create an output that details the polygon attributes that spatially relate to a point feature.

  • ArcView and ArcEditor Users:

    If the points layer is converted to polygons, then union the data and create a new feature class:

    1. In ArcToolBox, navigate to ArcToolBox > Analysis Tools > Proximity and select the Buffer tool. Use this tool to buffer the points and to convert them into a new polygon feature class.

    2. In ArcToolBox, navigate to ArcToolBox > Analysis Tools > Overlay and select the Union tool. Input the Point_Buffer with a rank of 1, and then input the Polygon feature class with a rank of 2.

    3. Open the attribute table of the unioned feature class. Navigate to Option > Select by Attributes and then use the following as the query:

    [FID_point_buffer] > -1

    Substitute 'FID_point_buffer' for the name of field that contains the buffered points original ObjectID.

    4. Close the attribute table

    5. Right-click on the Union Feature Class > Data > Export Data to export the selected features into a new layer.

    Note:
    The selected features are all the polygons that represented the original points. This process works by creating overlapping polygons to house the information from multiple polygons.

    For example, if a polygon that falls in the middle of two overlapping polygons, a new polygon will automatically be created to house the attributes from the second polygon. The original ObjectID for the points are housed in the new FID_Point field and the original ObjectID for the polygons is housed in the new FID_Polygon field.
  • ArcInfo users only:

    1. In ArcToolBox, navigate to ArcToolBox > Analysis Tools > Overlay and find the Identify tool. The Identify tool computes a geometric intersection of the Input Features and Identity Features. The Input Features or portions thereof that overlap Identity Features will get the attributes of those Identity Features.

    2. In the tool, specify the Points feature class and the Input feature and the Polygon feature as the Identity feature.

    Note:
    This tool creates overlapping points to house the information from multiple polygons.

    For example, if a point that falls in the middle of two overlapping polygons, the Identify tool will automatically create a second point to house the attributes from the second polygon. The original ObjectID for the points are housed in the new FID_Point field and the original ObjectID for the polygons is housed in the new FID_Polygon field.