Query Related Features

This sample demonstrates how to query related features from a FeatureLayer by using the queryRelatedFeatures() method. Each hexagon on the map represents one or more major cities in the U.S. Clicking on a hexagon will trigger a query for its related features, which will be displayed in a table added to the view's UI.

How it works

A function calls queryObjectIds() whenever the user clicks on the map, which returns the objectId of the corresponding hexagon in the layer.

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layer.queryObjectIds({
  geometry: point,
  spatialRelationship: "intersects",
  returnGeometry: false,
  outFields: ["*"]
})

We highlight the hexagon, then use the queryRelatedFeatures() method to query for the related features attached to this object id.

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return layer.queryRelatedFeatures({
  outFields: ["NAME", "SUM_POPULATION"],
  relationshipId: layer.relationships[0].id,
  objectIds: objectIds
});

Then, we get the attributes from the resulting FeatureSet and create a table element that can hold the resulting data.