Vip6 feature attribute - Githubissues

A Pull Request for a proposed addition of a FeatureAttribute type to replace the use of spatial indexes to link Precinct.SpatialBoundary to the external geospatial feature(s).

GIS personnel we've spoken with have raised concerns about solely using the geospatial shape index (the FID) due to inherent instability in the index values. See this KB article from ESRI. These values are often set arbitrarily and could change without obvious notice.

This proposal instead relies on a new repeating complexType, FeatureAttribute, to store a column name and value pair referencing the geospatial attribute table which will be used to identify the appropriate shape(s) to assign to the Precinct.

NOTE: the CSV related items have not yet been updated to support FeatureAttribute.

     <Precinct id="pre90111">
        <..>
        <SpatialBoundary>
          <ExternalGeospatialFeature>
            <ExternalFileId>ef1</ExternalFileId>
            <FileFormat>shp</FileFormat>
            <FeatureIdentifier>
              <FeatureAttribute>
                <Name>county-fips</Name>
                <Value>66</Value>
              </FeatureAttribute>
              <FeatureAttribute>
                <Name>precinct-name</Name>
                <Value>abc</Value>
              </FeatureAttribute>
              <FeatureAttribute>
                <Name>precinct-split-number</Name>
                <Value>123</Value>
              </FeatureAttribute>
            </FeatureIdentifier>
          </ExternalGeospatialFeature>
        </SpatialBoundary>
     </Precinct>

votinginfoproject / vip-specification

Vip6 feature attribute #423