Attribute Rule - Related Table - Foreign Key null return

DavidFotheringham1

I am attempting to get an attribute from a parent feature class into a child table using attribute rules.

I used this question as a basic. This issue that I have is that the filter does not work because the expression is not finding a value in my parent GUID which is populated by the relationship from the feature class.

Even this code does not work

var gid = $feature.parent_guid

return gid

Every other field in the table returns something. Just not the parent ID (the foreign key in the relationship). This is true if it is a true GUID or just some text (e.g. A)

Any help would be most appreciated. I am using Pro 2.9.1. It also did not work on 2.8

JohannesLindner

Are you absolutely sure that the field is actually named parent_guid?

If you have a relationship class connecting the two tables, you can also try to use FeatureSetByRelationshipName.

// calculation attribute rule on child
// field: if you want to get only one field from the parent, then chose 
// that field. if you want to get multiple fields, leave empty
// triggers: Insert(, update)

// load the related parent features using one of these methods
// if you have a relationship class between parent and child:
var parent_fs = FeatureSetByRelationshipName($feature, "RelationshipName")
// if not
var parent_fs = FeatureSetByName($datastore, "NameOfParentFC")
var key = $feature.ForeignKeyField
parent_fs = Filter(parent_fs, "PrimaryKeyField = @key")

// return nothing if no parent feature was found
var parent = First(parent_fs)
if(parent == null) { return }

// if you want to return only one field:
return parent.Field

// if you want to return multiple fields:
var att = {
  "Field1": parent.Field1,
  "Field2": parent.Field2
}
return {"result": {"attributes": att}}