Work with input data

Configure input dataIngest real-time dataIngest historical dataLocation parametersDate and time parametersFeed polling interval schedulingFeed to history feature layer

Feeds

Work with feedsFeed details and statusShare feedsAWS IoTAzure Event HubAzure Service BusBaron WeatherCisco Edge IntelligenceDTN WeatherGeotab (DeviceStatusInfo)Geotab (LogRecord)gRPCGTFSHAAS AlertFeature LayerFlightAware (Airborne)FlightAware (Surface)HTTP PollerHTTP ReceiverHTTP SimulatorKafkaMotive AVLMQTTPreCise MRMRabbitMQRSSSamsaraStream LayerTAK Client (Beta)TracPlusVectronic AerospaceVerizon Connect RevealWazeWebSocket

Data sources

Work with data sourcesAmazon S3Azure Blob StorageAzure Cosmos DBFeature LayerFeature Layer (archive)HTTP PollerRSSStandard geographies

Data formats

Supported data formatsDelimitedJSONEsri JSONGeoJSONXML

Troubleshoot

Common ingestion issues and solutions
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Feature Layer

In this topic

  1. Examples
  2. Usage notes
  3. Parameters
  4. Considerations and limitations

The Feature Layer source type in ArcGIS Velocity loads features from an ArcGIS Online or ArcGIS Server feature layer.

Examples

The following are example use cases for the data source:

  • A user selects an ArcGIS Online hosted feature layer containing the features to load.
  • A GIS analyst provides the URL to an ArcGIS Server feature layer (for example, https://sampleserver6.arcgisonline.com/arcgis/rest/services/Wildfire/FeatureServer/2) containing the features to load.
  • A user can add real-time weather conditions to their map by incorporating a weather feature layer from ArcGIS Online.

Usage notes

Keep the following in mind when working with the data source:

  • When browsing a feature layer item, you can filter by folders, favorites, groups, or organization. You can filter further by date modified, date created, and tags.
  • ArcGIS Server feature layers can also be loaded using a URL. Use an ArcGIS Server services directory REST URL (for example, https://sampleserver6.arcgisonline.com/arcgis/rest/services/Wildfire/FeatureServer/2). This URL should end in /FeatureServer/# or /MapServer/# in which # is the layer number.
  • To load a secured feature layer from a URL, first add items from the web to ArcGIS Online and store credentials, then browse to the registered ArcGIS Online item to load the secured feature layer.
  • Feature layers must have a unique identifier field. The unique identifier must not be null, must contain unique values, and must be one of the following data types:
    • Integer (32- and 64-bit positive values only)
    • String
    • GUID
    • Date
    • Date only
    • Time only
  • Feature layers must have a unique identifier that supports the Min and Max summary statistics operations. When using an ArcGIS Server feature layer, keep in mind that some service backends do not support virtual object ID fields, such as ESRI_OID.
  • The feature layer must be accessible on the internet.
  • If a field is provided for the Timestamp field parameter, the Feature Layer source queries the feature layer to only load features relevant to the current analytic run (scheduled analytics only).
    • If the Timestamp field value is provided, when the analytic is started the first time, Velocity polls the feature layer and loads all features with a timestamp field datetime less than the first scheduled run time that also meets the criteria of the WHERE clause. For each subsequent run, only features with a timestamp field value between the last scheduled run time and the current scheduled run time that also meets the criteria of the WHERE clause are loaded.
    • If no Timestamp field value is provided, each time the analytic is started, the Feature Layer feed loads all features from the feature layer as events to be processed.
  • A timestamp field cannot be specified when configuring a feature layer source in a real-time analytic, because each time the real-time analytic is started, the feature layer feed loads all features returned by the configured where clause.
  • After configuring the source connection parameters, refer to configuring input data to learn how to define the schema and the key parameters.

Parameters

The following are the parameters for the data source:

ParameterDescriptionData type
WHERE clause

A Structured Query Language (SQL) clause used to filter features loaded from the specified feature layer. The default is to load all features using 1=1 and can be modified to include specific attribute values and logic conditions.

Most feature layers support SQL-92 WHERE clause syntax on the fields in the layer

Feature layers generated by Velocity or feature layers in ArcGIS Enterprise running on a spatiotemporal big data store source have restrictions on what is supported; they only support a subset of SQL-92. The supported SQL-92 syntax with these feature layers are as follows:

  • ( '<=' | '>=' | '<' | '>' | '=' | '!=' | '<>' | LIKE )
  • (AND | OR)
  • (IS | IS_NOT)
  • (IN | NOT_IN) ( '(' ( expr ( ',' expr )* )? ')' )
  • COLUMN_NAME BETWEEN LITERAL_VALUE AND LITERAL_VALUE

If you're using analytic global variables to restrict feature loading, four global variables pertain to recurring big data analytics and are listed below. These variables can be used in conjunction with the feature layer source WHERE clause to only load certain features each time the big data analytic runs.

  • $analytic.AnalyticLastScheduledStartTime—The time the last run of the analytic was scheduled to start.
  • $analytic.AnalyticScheduledStartTime—The time the current run of the analytic was scheduled to start.
  • $analytic.AnalyticLastEndTime—The time the last run of the analytic ended.
  • $analytic.AnalyticStartTime—The time the current run of the analytic started. The difference between this and $analytic.AnalyticScheduledStartTime is the startup delay.

The most common workflow for using these variables is in conjunction with a real-time analytic that is continuously writing events to a feature layer output as the events occur.

Learn more about near real-time analysis

QueryString

Out fields

The fields from the feature layer that are loaded into Velocity.

The default is an asterisk (*), which denotes that all fields are loaded.

When specifying fields, use a comma-separated list of field names, for example: device_id,timestamp,horizontal_accuracy,latitude,longitude.

String

Output spatial reference

The well-known ID (WKID) of a spatial reference. The default is 4326.

String

Additional logging

(optional)

Specifies whether logging for raw requests issued by Velocity is available. The default is False.

Note:

Only turn on this parameter for troubleshooting purposes and turn it off when troubleshooting is complete. Contact Esri Technical Support for help with troubleshooting.

Boolean

Timestamp field

A date field for retrieving the latest features (scheduled analytics only).

Learn more about timestamp field settings

String

Considerations and limitations

Consider the following when using the data source:

  • The feature layer must be accessible on the internet.
  • Velocity does not reference layers that require credits to receive requests (ArcGIS Online).

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In this topic
  1. Examples
  2. Usage notes
  3. Parameters
  4. Considerations and limitations