Detect Incidents output error - The chosen join field name '*' does not exist in the Join Schema.

[MuneerMajid]

I am working with a Real time analytics to detect Vehicles on Site. I have an incoming feed from Azure Event Hub which streams the live locations of vehicles via a custom Dot Net app, and I have a Feature layer for boundaries of Geofences (Sites). 

I am using the spatial intersect open condition to detect when a vehicle enters a Geofence and these output incidents are saved in a Feature layer. However, when I try to introduce a join field to also include the name of the site (polygon) from the input geofence layer, I get an the below error - 

• The chosen join field name '*' does not exist in the Join Schema.
  
  

Below is the current schema of the output feature layer which was autogenerated by the Detect Incidents tool - 

If I remove the Parcel field and do not perform a join, the analytic works well and writes data to the output feature class just fine. Its critical for me to have the 'Parcel' Field in order to identify which site was visited.

Would really appreciate your inputs and advice. 

[JeffSilberberg]

So I don't belive that the Incident Detect function does not do what you want --

Try using a join and specifying a Summary Attribute (Name) and then a filter or Incident Detect after the join to determine if the transactions meet the criteria you have to continue processing.

https://doc.arcgis.com/en/iot/analyze/detect-incidents.htm

See the output layer information at the bottom of the page.  

[MuneerMajid]

I had to drop the output feature layer and recreate it as output to the Detect Incidents, it seems I did not have the join features enabled the first time since I have been incrementally building this up. I was hoping for the schema to be updated on the fly but this seems to be a limitation at this point. Once I recreated the Output feature layer, it imported the new schema with the join attribute as well. 

Thanks for the input. 

[JeffSilberberg]

Sounds correct -- 

Two things I have adopted as kind of a standard. First I do not auto-generate output schema but rather I manually build them in ArcGOL and then in the Analytics use Feature Layer Existing instead of new. Second,  even if I do let them auto-create the first time I drop a "select fields"  in front of the outputs so I can add and map various elements of the schema as needed without breaking/updating the outputs until I want to.