require(["esri/tasks/QueryTask", "esri/tasks/support/Query"], function(QueryTask, Query){
  var citiesLayerUrl = " ... "; // Represents the REST endpoint for a layer of cities.
  var queryTask = new QueryTask({
    url: citiesLayerUrl
  });
  var query = new Query();
  query.returnGeometry = true;
  query.outFields = ["*"];
  query.where = "POP > 1000000";  // Return all cities with a population greater than 1 million

  // When resolved, returns features and graphics that satisfy the query.
  queryTask.execute(query).then(function(results){
    console.log(results.features);
  });

  // When resolved, returns a count of the features that satisfy the query.
  queryTask.executeForCount(query).then(function(results){
    console.log(results);
  });

});

Property Overview

Property Details

declaredClassStringreadonly

The name of the class. The declared class name is formatted as esri.folder.className.

gdbVersionString

Specify the geodatabase version to display. Requires ArcGIS Server service 10.1 or greater.

requestOptionsObject

The options to be used for data requests. These options can also be controlled through the requestOptions method parameter.

urlString

The ArcGIS Server REST service URL (usually of a Feature Service Layer or Map Service Layer) for use in a task.

Method Overview

Method Details

execute(params, requestOptions){Promise}

Executes a Query against an ArcGIS Server map layer. The result is returned as a FeatureSet, which can be accessed using the .then() method. A FeatureSet contains an array of Graphic features, which can be added to the map. This array will not be populated if no results are found.

Parameters:

params Query Specifies the attributes and spatial filter of the query. This object may be autocast.

requestOptions Object optional Additional options to be used for the data request (will override requestOptions defined during construction).

Returns:

Type	Description
Promise	When resolved, a FeatureSet containing an array of graphic features is returned.

Example:

require([
  "esri/tasks/support/Query", "esri/tasks/QueryTask", ...
], function(Query, QueryTask, ... ) {
  var query = new Query();
  var queryTask = new QueryTask( ... );
  query.where = "STATE_NAME = 'Washington'";
  query.outSpatialReference = { wkid:102100 };
  query.returnGeometry = true;
  query.outFields = [ "CITY_NAME" ];
  queryTask.execute(query).then(function(results){
    // Results.graphics contains the graphics returned from query
  });
  ...
});

executeForCount(params, requestOptions){Promise}

Gets a count of the number of features that satisfy the input query. Valid only for layers published using ArcGIS Server 10 SP1 or greater. Layers published with earlier versions of ArcGIS Server return an error to the errback param of .then().

Parameters:

params Query Specifies the attributes and spatial filter of the query. This object may be autocast.

requestOptions Object optional Additional options to be used for the data request (will override requestOptions defined during construction).

Returns:

Type	Description
Promise	When resolved, the result is the number of features that satisfy the input query.

Example:

require([
  "esri/tasks/QueryTask", ...
], function(QueryTask, ... ) {
  var queryTask = new QueryTask( ... );
  queryTask.executeForCount({ // autocasts as esri/tasks/support/Query
     where: "POP90_SQMI < 100"
  }).then(function(count){
    console.log(count, " features matched the input query");
  }, function(error){
       console.log(error); // Will print error in console if unsupported layers are used
     });
});

executeForExtent(params, requestOptions){Promise}

Gets the extent of the features that satisfy the input query. The count of features that satisfy the input query is returned upon resolution as well. Valid only for hosted feature services on arcgis.com and for ArcGIS Server 10.3.1 and later.

Parameters:

params Query Specifies the attributes and spatial filter of the query. This object may be autocast.

requestOptions Object optional Additional options to be used for the data request (will override requestOptions defined during construction).

Returns:

Type	Description
Promise	When resolved, returns the extent and count of the features that satisfy the input query. See the object specification table below for details. Property Type Description count number The number of features that satisfy the input query. extent Extent The extent of the features that satisfy the query.

executeForIds(params, requestOptions){Promise}

Executes a Query against an ArcGIS Server map layer. The result is an array of the object IDs of features that satisfy the input query.

Parameters:

params Query Specifies the attributes and spatial filter of the query. This object may be autocast.

requestOptions Object optional Additional options to be used for the data request (will override requestOptions defined during construction).

Returns:

Type	Description
Promise	When resolved, the result is an array of object IDs for features that satisfy the input query.

Example:

require([
  "esri/tasks/QueryTask", ...
], function(QueryTask, ... ) {
  var queryTask = new QueryTask( ... );
  queryTask.executeForIds({ // autocasts as esri/tasks/support/Query
     where: "region = 'Southern California'"
  }).then(function(results){
    console.log(results);  // an array of object IDs
  });
  ...
});

executeRelationshipQuery(params, requestOptions){Promise}

Executes a RelationshipQuery against an ArcGIS Server map layer (or table). If the query is successful, the result is returned as a FeatureSet, which can be accessed using the .then() method.

Parameters:

params RelationshipQuery Specifies the attributes and spatial filter of the query.

requestOptions Object optional Additional options to be used for the data request (will override requestOptions defined during construction).

Returns:

Type	Description
Promise	When resolved, the results of this operation are and array of FeatureSet grouped by source layer (or table) object IDs. Each FeatureSet contains an array of Graphic features including the values of the fields requested by the user. This array will not be populated if no results are found.