ESRI Javascript FeatureLayer Select by Attributes

Question

I am trying to select a group of features in an ESRI javascript API featureLayer by attribute. The call errors out. My code is as follows. Here is the layer definition:

 var fieldDefs = [{
 "name": "county",
 "type": "esriFieldTypeString",
 "alias": "county"
 },
 {
 "name": "pop",
 "type": "esriFieldTypeInteger",
 "alias": "pop"
 },
 "name": "ObjectID",
 "alias": "ObjectID",
 "type": "esriFieldTypeOID"
 }
 ];
 var featureCollection = {
 "layerDefinition": null,
 "featureSet": {
 "features": [],
 "geometryType": "esriGeometryPolygon";
 }
 };
 var featureCollection.layerDefinition = {
 "geometryType": "esriGeometryPolygon";,
 "objectIdField": "ObjectID",
 "drawingInfo": {
 "renderer": {
 "type": "simple",
 "symbol": symbol
 }
 },
 "fields": fieldDefs
 };
 var featureLayer = new FeatureLayer(featureCollection, {
 id: idString,
 mode: FeatureLayer.MODE_SNAPSHOT,
 fields: fieldDefs
 });

I then populate the layer using applyEdits and later query the layer using this function:

queryCounty = function(county_name) {
 var query = new Query();
 query.where = "county = '" + county_name + "'";
 //projectsOverlayMap.clearSelection();
 console.log("WHERE: " + "county = '" + county_name + "'");
 projectsOverlayMap.selectFeatures(query, FeatureLayer.SELECTION_NEW, function(results){
 alert(results.length);
 });

And calling it like this:

queryCounty("Jefferson");

When I do that I get the following error:

"Error: FeatureLayer::selectFeatures - query contains one or more unsupported parameters

There are some decent on line examples of this function using geometry queries but none that I have found that use and attribute query. What am I missing?

• vinayan: has it got anything to do with gis.stackexchange.com/a/112438/5850

Answer 1

Are you creating featurelayer by FeatureLayer(featureCollectionObject, options?)?

If yes there are some restriction for the featurelayer object. You cannot execute queries on such layers.

See the docs https://developers.arcgis.com/javascript/jsapi/featurelayer-amd.html#featurelayer2

• Frank Conry: The doc says "Does not support queries that need to be performed on the server" since I'm in snapshot mode, everything is persisting on the client, right? All the features are loaded in with attributes already, there is no serverside component.
• Shabeerali: I thinks the query with where will work only with feature layer that has from server.Refer the thread geonet.esri.com/thread/14137 For testing try to execute the query with objectid

Answer 2

It's clunky but you can query on the extent of the map and then loop through the results to get the attributes you want. For example:

require(['esri/tasks/query', 'esri/layers/FeatureLayer'], function (Query, FeatureLayer) {
 var query = new Query();
 query.geometry = projectsOverlayMap.extent;
 featureLayer.selectFeatures(query, FeatureLayer.SELECTION_NEW, function (results) {
 for(var key in results) {
 if(results[key].attributes['county'] === county_name) {
 ... do something ...
 }
 }
 });
}