Feature Layer (new)

The Feature Layer (new) output in ArcGIS Velocity allows you to write output features to a new ArcGIS feature layer. When writing to this output type, either a spatiotemporal feature layer and map image layer or an ArcGIS Online hosted feature layer is created. Once the layer or layers are created, they are available for use in Velocity and your ArcGIS Online organization, where they can be added to maps, applications, and more.

Feature layers created by Velocity have key differences from other ArcGIS Online hosted feature layers, including the following:

• The associated data is stored in a spatiotemporal feature layer. As a result, the corresponding map image layer provides dynamic rendering and on-the-fly aggregation.
• A data retention policy must be defined for deleting older data from the feature layer. Data retention options can be set to 1 hour, 1 day, 1 week, 1 month, 6 months, and 1 year. Any feature layer with data that grows over time requires a value be specified in the Data retention (time period for retaining data) parameter. For example, if the Data storage method parameter is set to Add all new features and each time the analytic is run, you enable the Keep existing features and schema option, you need to set the data retention option.

  Learn more about data retention

• Older data can be exported to a feature layer archive before being deleted using the Data retention (time period for retaining data) parameter. Data exported to the feature layer archive is maintained for one year from the date of the export.
• There are some restrictions on the number of records that can be written to ArcGIS Online hosted feature layer outputs, including the following:
  • Real-time analytic output—When writing to an ArcGIS Online hosted feature layer from Velocity real-time analytics, no more than 120 events per minute can be written.
  • Runs once big data analytic output—Up to 50,000 records can be written to an ArcGIS Online hosted feature layer output.
  • Scheduled/recurring big data analytic output—The number of records that can be written to an ArcGIS Online hosted feature layer output depends on the run frequency of the analytic. For each minute between each run, 120 records can be written per minute. For example, an analytic that runs every minute can write 120 output features per run. An analytic that runs every 5 minutes can write 600 output features per run. An analytic that runs every 30 minutes can write 3,600 output features per run.

Examples

The following are example uses of the Feature Layer (new) output:

• After ingesting event data from IoT sensors in a feed and a real-time analytic, you want to store the features in a new feature layer.
• After performing analysis in a big data analytic, you want to write the resulting analysis features to a new feature layer.
• You have configured a feed within a real-time analytic to process events as they occur. You only want to store the latest state of your features as identified by the track ID in a new feature layer.

Usage notes

Keep the following in mind when working with the Feature Layer (new) output:

• If you enable the Keep existing features and schema option each time the analytic is run, the features written to the new output feature layer must maintain a consistent schema.
• The new feature layer and map image layer created by the output do not appear until the analytic is started and has successfully generated the output.
• A data retention strategy must be specified in the Data retention (time period for retaining data) parameter. The Data retention (time period for retaining data) and Data export (feature layer archive) options do not apply if you enable the Replace existing features and schema option each time the analytic is run.
• When editor tracking is enabled and the Data storage method parameter is set to Add all new features, the creator and editor user and date is always the same. If the Data storage method parameter is set to Keep only latest feature for each Track ID value, a track observation that is updated only has the editor user and date updated after the first observation.

Parameters

The following are the parameters for the Feature Layer (new) output:

Parameter	Description	Data type
Feature layer name	The name of the new feature layer.	String
Store data in spatiotemporal feature layer	After configuring source connection parameters, define the schema and the key parameters. If this parameter is unchecked (false), data will be written to a hosted feature layer in your organization and its storage will consume credits. Learn more about Considerations and limitations	Boolean
Data storage method	Specifies whether all new features are added to the feature layer or existing features are updated. Options include the following: Add all new features—All new features are added to the feature layer. Keep only latest feature for each Track ID value—Only the latest feature for each unique track ID is kept. If chosen, the output data schema should have a Track ID and Start Time key fields identified.	Boolean Note: If Keep latest feature is chosen, the value is true.
Each time the analytic runs	Specifies how existing data in the feature layer is dealt with each time the analytic is started. Options include the following: Keep existing features and schema—Each time the real-time analytic is started, existing features and schema are maintained. The new feature is appended to the existing data. Replace existing features and schema—Each time the analytic is started, the features and schema present in the feature layer are discarded and new features and schema are written.	Boolean Note: If Replace existing features and schema is chosen, the value is true.
Aggregation styles	Specifies the bin styles to enable for dynamic aggregation of the data. The bin styles are populated by default and can be modified. Bin styles can be defined for additional spatial references or projections. This parameter is only applicable when data is stored in a spatiotemporal feature layer.	Geohashes
Editor tracking	Enables editor tracking on the output feature layer. Editor tracking sets the username and date when feature records are created or updated in the output feature layer. Enabling this parameter appends the created_date, created_user, last_edited_date, and last_edited_user fields to the feature layer schema. This parameter is only applicable when data is stored in a spatiotemporal feature layer.	Boolean
Creator and editor username	Specifies the creator or editor username for processed data. The username can be derived from a field of the incoming data or set as the username of the analytic owner. The Creator and editor username parameter does not apply if the Editor tracking parameter has been disabled. Learn more about usage notes This parameter is only applicable when data is stored in a spatiotemporal feature layer.	String
Feature Service Portal Item ID	The portal item ID of the corresponding feature layer item created in ArcGIS Online. This parameter is not displayed when configuring the output and cannot be populated or modified. It is automatically populated by ArcGIS Velocity.	String
Map Service Portal Item ID	The portal item ID of the corresponding map layer item created in ArcGIS Online. This parameter is not displayed when configuring the output and cannot be populated or modified. It is automatically populated by Velocity. This parameter is only applicable when data is stored in a spatiotemporal feature layer.	String
Data retention (time period for retaining data)	Specifies the data retention strategy, or time period after which older data is deleted from the feature layer. Options include the following:1 hour 1 day, 1 week, 1 month, 6 months, and 1 year. Learn more about usage notes This parameter is only applicable when data is stored in a spatiotemporal feature layer.	String
Data export (feature layer archive)	Specifies whether purged data is exported to a feature layer archive before being purged. Options include the following: Do not export data and Export data. Data exported to the feature layer archive is maintained for one year from the date of the export. The Data retention (time period for retaining data) parameter does not apply if the Replace existing features and schema option is chosen. This parameter is only applicable when data is stored in a spatiotemporal feature layer.	String

Considerations and limitations

The following are considerations and limitations when using the Feature Layer (new) output:

• Feature layers hosted by Velocity cannot be shared publicly.
• If you choose the Keep existing features and schema option, each time the analytic is run, the features written to the new output feature layer should maintain a consistent schema.
• If the Store data in spatiotemporal feature layer parameter is unchecked, a hosted feature layer is created to store data. This storage will consume credits. It is important to also note the following:
  • Real-time analytic restrictions for ArcGIS Online hosted feature layer outputs include the following:
    • Features are written from Velocity real-time analytics to the hosted feature layer once every 60 seconds.
    • A maximum of 120 events can be written to the hosted feature layer per minute. Therefore, the average output data rate over time should not exceed 120 events per minute, or 2 events per second.
    • If an analytic produces more than 120 feature updates in one minute, excess features are stored in a temporary cache and written to the hosted feature layer during the next edit operation. Temporal order is maintained as features are emptied from the cache. The cache is maintained for up to 1,200 features, after which new records can be dropped while the cache is emptied.
    • When using the Keep only latest feature for each Track ID value storage option, if there is more than one observation for a given track ID in one minute, only the latest feature for that track is written to the hosted feature layer. The additional observations for the track do not count toward the 120 edits per minute maximum. In other words, higher-velocity ingestion can be supported with this storage option if there are 120 or fewer unique assets or devices being tracked.
  • Big data analytic restrictions for ArcGIS Online hosted feature layer outputs include the following:
    • Features are written from Velocity big data analytics to the hosted feature layer at the end of each run.
    • Non-scheduled big data analytics that run once write up to 50,000 records to an ArcGIS Online hosted feature layer output.
    • Big data analytics that are scheduled or run periodically control how many output features can be written to an ArcGIS Online hosted feature layer output depending on the run frequency. For each minute between each run, 120 records can be written per minute. For example, an analytic that runs every minute can write 120 output features per run, an analytic that runs every 5 minutes can write 600 output features per run, and an analytic that runs every 30 minutes can write 3,600 output features per run.
• Currently, big data analytics that run once can only write output to ArcGIS Online hosted feature layers in the WGS84 (4326) spatial reference. Use the Project tool before this output if necessary.
• The feature layer (and map image layer) portal items associated with the Feature layer (new) output must be owned by the creator for Velocity to write to the output. To change ownership of an item, reconfigure the analytic to write to an existing feature layer using the Feature Layer (existing) output.