What are table feature queries?
To access featuresquery operation. To do so, you can use ArcGIS Maps SDKs
You use table features queries to:
- Access a subset of features in a table
- Request features with a SQL WhereClause query
- Return features in different data formats e.g. JSON, GeoJSON, and PBF
- Return all or a subset of attribute fields for features
- Return features without geometries
How to query table features
The steps to access and query features are:
- Find the service URL for the feature layer to query.
- Define the
querySQL parameters (where clause). - Define the output parameters (data format).
- Execute the
query.
Types of queries
In general, the two types of feature queries you can implement are repeatable queries and unique queries.
Repeatable query
A repeatable query is a query you send to a feature servicecache to ask the service to cache the results.
Below is an example of a repeatable query with a repeatable where clause:
https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/LA_County_Parcels/FeatureServer/0/query?f=pbf&cacheHint=true&resultRecordCount=100&where=UseType = 'Irrigated Farm'&outFields=APN,UseType,TaxRateCity,TaxRateArea,Roll_LandValue&returnGeometry=false&token=<ACCESS_TOKEN>Unique query
A unique query is a query you send to a feature servicecache to ask the service to cache results from unique queries.
Below is an example of a unique query with a user-defined geometry:
https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/LA_County_Parcels/FeatureServer/0/query?f=pbf&geometry={"rings":[[[-13228576.521843342,4033084.7250306536],[-13222485.595442941,4033084.7250306536],[-13222485.595442941,4030103.75557307],[-13228576.521843342,4030103.75557307],[-13228576.521843342,4033084.7250306536]]]}&outFields=APN,UseType,TaxRateCity,Roll_LandValue&spatialRel=esriSpatialRelIntersects&geometryType=esriGeometryPolygon&token=<ACCESS_TOKEN>Feature queries and caches
When you query and/or display featuresquery request that is stored and managed so it can be reused by clients. Response caches are only beneficial to applications that make repeatable queries. Making use of response caches improves both performance and scalability allowing your application to perform well even when experiencing high load.
There are multiple levels of caches available to applications. This includes the following:
- Client-side cache: A response cache stored and managed by a web browser, native application, or operating system.
- CDN cache: A response cache stored and managed by CDN servers worldwide (ArcGIS Location Platform and ArcGIS Online only). This cache is configurable.
- Feature tile cache: A response cache stored and managed internally by the feature service.
All three levels of caches can exist at the same time. How the caches are used by an application, however, depends on the type of API you are using, the CDN cache max age settings you apply, and the parameters you include with the request.
In general, when a query request is sent to a feature service, the response caches are accessed in the following order:
- Client-side cache (if available)
- CDN cache (if available)
- Feature tile cache (if available)
If a cache is available, the response cache is sent back to the client immediately. If a cache isn't available, the request will look for the next level of cache that is available. If no caches are found, the query is processed by the feature service
Client-side cache
A client-side cache is the response data from queries to the feature service stored in a web browser, native application, or operating system. If the cache is available, the applications use this cache first before making requests to the feature service. When using the cache, the ArcGIS Maps SDKs
CDN cache
A CDN cache is the response data from queries stored on CDN servers around the world. The CDN caches the data returned from the service for requests for a length of time (cache) that you specify in the hosted feature layer
CDN caches are only available when using ArcGIS Location Platform
Feature tile cache
A feature tile is a data structure that contains the results of a query request stored in the server. A feature tile is created when a query request contains result or cache. The tiles can be sent directly back to the client to satisfy a query request or stored in a feature tile cache, CDN cache, or client-cache for future use.
A feature tile cache is the response data from queries stored at the service level as one or more feature tiles. A feature service cache is used when a client application sends consistent and repeatable queries to a feature service and the service stores the results as feature tiles for future use. The ArcGIS Maps SDK
Feature tile caches are available when using ArcGIS Location Platform
URL request
https://{host}/{organizationID}/ArcGIS/rest/services/{serviceName}/FeatureServer/{id}/query?{queryParameters}Required parameters
| Name | Description | Examples |
|---|---|---|
f | The format of the data returned. | f=json f=pjson f=geojson f=pbf f=html |
token | An API key or OAuth 2.0 access token | token= |
SQL parameters
Use this parameter to define a WhereClause for a SQL query.
| Name | Description | Examples |
|---|---|---|
where | A SQL clause that defines which data to return based upon attributegeometry and spatial parameters. Learn more about the SQL-92 format here. |
Output parameters
Use these parameters to define and optimize the query response.
| Name | Description | Examples |
|---|---|---|
out | A list of field names that specifies the attributesout). The more fields you request, the larger the attributes portion of the response JSON payload and the longer it could take to download. Only request the fields you need for display or analysis. To return all fields, which can be useful during development and testing, use out. | |
order | Order the records that are included in the response by specifying which fields to sort by and a sort order for each field: - ASC - ascending order (default)- DESC - descendingFor example, order. |
Cache parameters
| Name | Description | Examples |
|---|---|---|
cache | Ask the service to store the query response for later use. This should only be used when client applications send consistent and repeatable queries. Using cache can significantly improve performance. See the Query a feature layer (SQL) example. | cache cache |
Pagination parameters
Use these parameters to paginate through records that are beyond the services max property.
| Name | Description | Examples |
|---|---|---|
result | The number of records to return from a query, if not specified the service defaults to max. | result |
result | Skip this number of records and start from the next record (that is, resultOffset + 1). The default is 0. | result |
Code examples
Query all features
To query and display featuresout is used in the query.
Steps
- Get the hosted table URL and layer ID.
- Add the hosted table and define the fields.
- Display the fields and records.
const q = trailsLayer.createQuery();
q.where = "1=1";
q.cacheHint = true;
q.outFields = Object.keys(outFields);
trailsLayer.queryFeatures(q).then(loadTable);
SQL query for features
To search for featureswhere clause. In the example below, a where clause is used to return parcel features from a table based on input values. Since these queries are unknown and unique based on user input they should not be cached.
Steps
- Get the hosted table URL and layer ID.
- Create and execute a SQL query.
- Display the records.
const parcelQuery = {
where: whereClause,
outFields: Object.keys(outFields), // Attributes to return
orderByFields: ["yearbuilt1 ASC", "sqftmain1 ASC"],
};
parcelsTable.queryFeatures(parcelQuery).then((resp) => {
document.getElementById("resultCountLabel").innerHTML =
`${resp.features.length} records returned`;
addToTable(resp, true);
setLoading(false);
});
REST API
curl https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Santa_Monica_parcels_table/FeatureServer/0/query? \
-d "where=yearbuilt1 >= 2019 and sqftmain1 >= 4000 and bedrooms1 <= 4 and bathrooms1 >= 3" \
-d "outFields=usetype, ain, situsfulla, yearbuilt1, sqftmain1, bedrooms1, bathrooms1" \
-d "f=json"Query features with paging
The maximum number of features returned by a single query to a hosted feature layer is constrained by the services max property. You can use pagination to return features that exceed the maxRecordCount. This example uses paged queries to return features in sets of 100 based on object id.
To learn more, visit the REST services documentation.
Steps
- Get the hosted table item ID
An item ID is a unique identifier representing a single item stored, managed, and accessed in a portal, such as a web map, hosted layer, or file. or URL and layer ID. - Set the
result, andRecord Count resultparameters of the query and execute.Offset - Display the paginated records.
APIs
// create initial query params
const queryParams = {
where: "1=1",
outFields: Object.keys(appParams.outFields),
orderByFields: ["FID asc"],
returnGeometry: true,
num: appParams.returnCount, // number of records to return
start: appParams.currentPage, // offset for pagination
};
/**
* Set current page and send query request to the server
*/
const queryFeatures = () => {
// set the page to retrieve
queryParams.start = appParams.currentPage; // set offset based on what page to return
parcelsLayer.queryFeatures(queryParams).then(displayResults);
};
REST API
curl "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Santa_Monica_public_parcels/FeatureServer/0/query?" \
-d "f=json" \
-d "&token={ACCESS_TOKEN}" \
-d "&where=1=1" \
-d "&outFields=FID, ain, situsfulla, usetype" \
-d "&orderByFields=FID ASC" \
-d "&resultRecordCount=100" \
-d "&resultOffset=0"Join a table to a feature layer
You can combine the attributes from one dataset to another based on attribute relationships which creates new feature dataJoin operation from the spatial analysis service
Steps
- Get the hosted table URL.
- Get the feature layer URL.
- Join the feature table to the feature layer.
- Display the resulting layer from the join.
APIs
const trailsResults = await trailsLayer.load().then(() => {
return trailsLayer.queryFeatures({
where: "1=1",
returnGeometry: true,
outFields: ["TRL_NAME"],
});
});
const tableResults = await tableLayer.load().then(() => {
return tableLayer.queryFeatures({
where: "1=1",
outFields: ["*"],
returnGeometry: false,
});
});
const joinedAttFeatures = [];
trailsResults.features.forEach((trailsFeature) => {
tableResults.features.forEach((tableFeature) => {
if (
trailsFeature.attributes["TRL_NAME"] ===
tableFeature.attributes["TRL_NAME"]
) {
trailsFeature.attributes = {
...trailsFeature.attributes,
...tableFeature.attributes,
};
joinedAttFeatures.push(trailsFeature.clone());
}
});
});
const joinedLayer = new FeatureLayer({
id: "joined-layer",
source: joinedAttFeatures,
objectIdField: "ObjectId2",
fields: tableLayer.fields,
title: "Joined Layer",
geometryType: "point",
outFields: ["*"],
});
map.add(joinedLayer);
// Add layer to the feature table widget
const featureTable = new FeatureTable({
view: view,
layer: joinedLayer,
container: tableDiv,
hiddenFields: ["OBJECTID"],
});
Service requests
Request
POST arcgis.com/sharing/rest/portals/self HTTP/1.1
Content-Type: application/x-www-form-urlencoded
&f=json
&token=<ACCESS_TOKEN>Response (JSON)
{
"helperServices": {
// Other parameters
"analysis": {
"url": "https://<YOUR_ANALYSIS_SERVICE>/arcgis/rest/services/tasks/GPServer"
},
"geoenrichment": {
"url": "https://geoenrich.arcgis.com/arcgis/rest/services/World/GeoenrichmentServer"
}
}
}Tutorials
Add a feature layer
Access and display point, line, and polygon features from a feature service.
Add a vector tile layer
Add a map tile layer
Style a feature layer
Use symbols and renderers to style feature layers.
Query a feature layer (spatial)
Execute a spatial query to get features from a feature layer.
Query a feature layer (SQL)
Execute a SQL query to access polygon features from a feature layer.
Edit feature data
Display a popup
Format a popup to show attributes in a feature layer.
Workflows
Create a feature service for an app
Learn how to import parcel data, create and style a feature layer, and then access the features in an app.
Create a feature layer view for an editor app
Learn how to import parcel data, create and style a feature layer view, and then access the features in an editing app.
Create a vector tile service for an app
Learn how to import parcel data, style a feature layer, and then create a vector tile service for an app.
Create a map tile service for an app
Learn how to import contour data, style a feature layer, and create a map tile service for an app.
Services
Feature service
Add, update, delete, and query feature data.
Vector tile service
Store and access vector tile data.
Map tile service
Store and access map tile data.
Image service
Store and access imagery and raster data.
API support
Use data management tools
- 1. Use portal class and direct REST API requests
- 2. Access via ArcGIS REST JS
- 3. Requires manually setting styles for renderers