The ArcGIS Velocity real-time and big data analytics provide a variety of standard geography sources to aid in the filtering and enrichment of event data. The standard geography layers provided are stored in ArcGIS Online hosted feature layers. As a result, when configuring the standard geography layer, you can modify the feature layer parameters including Where Clause, Out Fields, and Output Spatial Reference.
Examples
The following are example scenarios when standard geography sources are useful:
- A researcher wants to spatially filter records from hundreds of delimited text files to find only the features that occur in a certain state.
- A GIS analyst wants to enrich incoming sensor location events to tag the ZIP Code area where the event occurred.
Standard geography layers
The standard geography layers are provided in two groups: World and United States.
- World
- World Country Areas
- World Regions
- World Administrative Divisions
- United States
- US States
- US Counties
- US Zip Code Areas
- US Census Tracts
- US Census Block Groups
Parameters
The following table lists the feature layer parameters:
| Parameter | Explanation | Data Type |
|---|---|---|
Where Clause | A where clause that filters features loaded from the specified standard geography layer. The default is to load all features using 1=1. The default clause can be modified to include specific attribute values and logic conditions. SQL 92 WHERE clause syntax on the fields in the layer is supported for standard geography feature layers. | QueryString |
Out Fields | The fields from the standard geography feature layer that will be loaded into Velocity. The default value is an asterisk (*), which denotes that all fields will be loaded. To indicate specific fields, use comma-separated field names. The following is an example: OBJECTID,device_id,timestamp,horizontal_accuracy,latitude,longitude | String |
Output Spatial Reference | The well-known ID (WKID) of a spatial reference. The default is 4326. Velocity will load data from the feature layer in the spatial referenced defined by this parameter. | String |