ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Desktop.Editing Namespace / KnowledgeGraphRelationshipDescription Class
Members Example

In This Topic
    KnowledgeGraphRelationshipDescription Class
    In This Topic
    Represents a relationship between two entities in a knowledge graph.
    Object Model
    KnowledgeGraphRelationshipDescription ClassRowHandle ClassRowHandle Class
    Syntax
    public sealed class KnowledgeGraphRelationshipDescription : BaseRelationshipDescription 
    Public NotInheritable Class KnowledgeGraphRelationshipDescription 
       Inherits BaseRelationshipDescription
    Remarks
    A KnowledgeGraphRelationshipDescription is used to create and delete a relationship between two rows defined by a ArcGIS.Core.Data.Knowledge.KnowledgeGraphRelationshipType. Once defined, use EditOperation.Create to create the relationship and EditOperation.Delete to remove the relationship.
    Example
    Create a new Relationship from Existing Entities 2
    var create_rel2 = await QueuedTask.Run(() =>
    {
      //Instantiate an operation for the Create
      var edit_op = new EditOperation()
      {
        Name = "Create a new relationship record",
        SelectNewFeatures = true
      };
    
      //Use datasets or feature layer(s) or standalone table(s)
      //Get a reference to the KnowledgeGraph
      //var kg = ... ; 
    
      //We will use a relate called 'HasEmployee' to relate an Organization w/ a Person
      //Use either tables or map members to get the rows to be related...
      var org_fc = kg.OpenDataset<FeatureClass>("Organization");
      var person_tbl = kg.OpenDataset<Table>("Person");
    
      //Get the relationship dataset
      //We can use either a table or standalone table
      var emp_tbl = kg.OpenDataset<Table>("HasEmployee");
    
      // get the origin, destination records
      Guid guidOrigin = Guid.Empty;
      Guid guidDestination = Guid.Empty;
      using (var rc = org_fc.Search())
      {
        if (rc.MoveNext())
          //Use the KnowledgeGraphPropertyInfo to avoid hardcoding...
          guidOrigin = rc.Current.GetGlobalID();
      }
      using (var rc = person_tbl.Search())
      {
        if (rc.MoveNext())
          //Use the KnowledgeGraphPropertyInfo to avoid hardcoding...
          guidDestination = rc.Current.GetGlobalID();
      }
    
      //Add any extra attribute information for the relation as needed
      var attribs = new Dictionary<string, object>();
      attribs["StartDate"] = new DateTimeOffset(DateTime.Now);
    
      var rd = new KnowledgeGraphRelationshipDescription(guidOrigin, guidDestination, attribs);
      //Add a create for the relationship to the operation
      edit_op.Create(emp_tbl, rd);
    
      //Do the create
      return edit_op.Execute();
    });
    
    Create a new Relationship and New Entities 2
    var createRel = await QueuedTask.Run(() =>
    {
      //This example uses a KnowledgeGraphRelationshipDescription
      var edit_op = new EditOperation()
      {
        Name = "Create entities and a relationship using a KG relate desc",
        SelectNewFeatures = true
      };
    
      //We are just going to use mapmembers in this example
      //we could equally use feature classes/tables
      var kg_layer = mv.Map.GetLayersAsFlattenedList()?
                    .OfType<ArcGIS.Desktop.Mapping.KnowledgeGraphLayer>().First();
      //From the KG Layer get the relevant child feature layer(s) and/or standalone
      //table(s)
      var org_fl = kg_layer.GetLayersAsFlattenedList().OfType<FeatureLayer>()
                      .First(child_layer => child_layer.Name == "Organization");
    
      var person_stbl = kg_layer.GetStandaloneTablesAsFlattenedList()
                      .First(child_layer => child_layer.Name == "Person");
    
      var rel_stbl = kg_layer.GetStandaloneTablesAsFlattenedList()
                      .First(child_layer => child_layer.Name == "HasEmployee");
    
      var attribs = new Dictionary<string, object>();
    
      //New Organization
      attribs["Name"] = "Acme Ltd.";
      attribs["Description"] = "Specializes in household items";
      attribs["SHAPE"] = org_location;
    
      //Add it to the operation - we need the rowtoken
      var rowtoken_org = edit_op.Create(org_fl, attribs);
    
      attribs.Clear();//we are going to re-use the dictionary
    
      //New Person
      attribs["Name"] = "Bob";
      attribs["Age"] = "41";
      attribs["Skills"] = "Plumbing, Framing, Flooring";
    
      //Add it to the operation
      var rowtoken_person = edit_op.Create(person_stbl, attribs);
    
      attribs.Clear();
    
      //Create the new relationship using a KnowledgeGraphRelationshipDescription
      //Row handles act as the placeholders for the TO BE created new entities that will
      //be related
      var src_row_handle = new RowHandle(rowtoken_org);
      var dest_row_handle = new RowHandle(rowtoken_person);
    
      //Add any extra attribute information for the relation as needed
      attribs["StartDate"] = new DateTimeOffset(DateTime.Now);
    
      var rel_desc = new KnowledgeGraphRelationshipDescription(
                                  src_row_handle, dest_row_handle, attribs);
    
      //Add the relate description to the edit operation
      edit_op.Create(rel_stbl, rel_desc);
    
      //Execute the create of the entities and relationship
      return edit_op.Execute();
    });
    
    Delete a Relationship record 2
    await QueuedTask.Run(() =>
    {
    
      var edit_op = new EditOperation()
      {
        Name = "Delete a Relationship record"
      };
    
      //We are  going to use mapmembers in this example
      //we could equally use feature classes/tables
      var kg_layer = mv.Map.GetLayersAsFlattenedList()?
                    .OfType<ArcGIS.Desktop.Mapping.KnowledgeGraphLayer>().First();
    
      //entities
      var entityOrg = kg_layer.GetStandaloneTablesAsFlattenedList()
                      .First(child_layer => child_layer.Name == "Organization");
      var entityPerson = kg_layer.GetStandaloneTablesAsFlattenedList()
                      .First(child_layer => child_layer.Name == "Person");
    
      //Relationship
      var rel_stbl = kg_layer.GetStandaloneTablesAsFlattenedList()
                      .First(child_layer => child_layer.Name == "HasEmployee");
    
      // get the origin, destination records
      Guid guidOrigin = Guid.Empty;
      Guid guidDestination = Guid.Empty;
      using (var rc = entityOrg.Search())
      {
        if (rc.MoveNext())
          //Use the KnowledgeGraphPropertyInfo to avoid hardcoding...
          guidOrigin = rc.Current.GetGlobalID();
      }
      using (var rc = entityPerson.Search())
      {
        if (rc.MoveNext())
          //Use the KnowledgeGraphPropertyInfo to avoid hardcoding...
          guidDestination = rc.Current.GetGlobalID();
      }
    
      var rd = new KnowledgeGraphRelationshipDescription(guidOrigin, guidDestination);
      edit_op.Delete(rel_stbl, rd);
      edit_op.Execute();//Do the delete
    });
    Inheritance Hierarchy

    System.Object
       ArcGIS.Desktop.Editing.BaseRelationshipDescription
          ArcGIS.Desktop.Editing.KnowledgeGraphRelationshipDescription

    Requirements

    Target Platforms: Windows 11, Windows 10

    ArcGIS Pro version: 3.4 or higher.
    See Also