ArcGIS Pro 3.7 API Reference Guide
ArcGIS.Core.Data.DDL Namespace / SchemaBuilder Class / Create Method / Create(KnowledgeGraphTypeDescription) Method
Example

In This Topic
    Create(KnowledgeGraphTypeDescription) Method
    In This Topic
    Enqueue the create operation on the object referred to by the ArcGIS.Core.Data.DDL.Knowledge.KnowledgeGraphTypeDescription. This method must be called on the MCT. Use QueuedTask.Run.
    Syntax
    Exceptions
    ExceptionDescription
    namedObjectTypeDescription is null
    A KnowledgeGraph must be set as the datasource for this operation
    This method or property must be called within the lambda passed to QueuedTask.Run.
    Remarks
    An object id and global id property are always added to new named object types whether explicitly specified in the namedObjectTypeDescription or not. In addition, the required origin id and destination id fields are also automatically added to all new relationship named object types (also whether explicitly specified or not). A shape description is optional. However, if the namedObjectTypeDescription includes a shape description then its spatial reference must match the spatial reference of the knowledge graph datasource (in which it is being created).
    Example
    Creating a table with index from scratch
    {
      // Must be called within QueuedTask.Run
      void CreatingTableWithIndex(SchemaBuilder schemaBuilder)
      {
        FieldDescription nameFieldDescription = FieldDescription.CreateStringField("Name", 50);
        FieldDescription addressFieldDescription = FieldDescription.CreateStringField("Address", 200);
    
        // Creating a feature class, 'Buildings' with two fields
        TableDescription tableDescription = new TableDescription("Buildings",
          new List<FieldDescription>() { nameFieldDescription, addressFieldDescription });
    
        // Enqueue DDL operation to create a table
        TableToken tableToken = schemaBuilder.Create(tableDescription);
    
        // Creating an attribute index named as 'Idx'
        AttributeIndexDescription attributeIndexDescription = new AttributeIndexDescription("Idx", new TableDescription(tableToken),
          new List<string> { nameFieldDescription.Name, addressFieldDescription.Name });
    
        // Enqueue DDL operation to create an attribute index
        schemaBuilder.Create(attributeIndexDescription);
    
        // Execute build indexes operation
        bool isBuildSuccess = schemaBuilder.Build();
      }
    }
    Adding indexes in pre-existing dataset
    {
      // Must be called within QueuedTask.Run
      void AddingIndexes(SchemaBuilder schemaBuilder, FeatureClassDefinition featureClassDefinition)
      {
        // Field names to add in the attribute index
        string fieldName = featureClassDefinition.GetFields().First(f => f.AliasName.Contains("Name")).Name;
        string fieldAddress = featureClassDefinition.GetFields().First(f => f.AliasName.Contains("Address")).Name;
    
        // Creating an attribute index with index name 'Idx' and two participating fields' name
        AttributeIndexDescription attributeIndexDescription = new AttributeIndexDescription("Idx",
          new TableDescription(featureClassDefinition), new List<string> { fieldName, fieldAddress });
    
        // Enqueue DDL operation for an attribute index creation 
        schemaBuilder.Create(attributeIndexDescription);
    
        // Creating the spatial index 
        SpatialIndexDescription spatialIndexDescription = new SpatialIndexDescription(new FeatureClassDescription(featureClassDefinition));
    
        // Enqueue DDL operation for the spatial index creation
        schemaBuilder.Create(spatialIndexDescription);
    
        // Execute build indexes operation
        bool isBuildSuccess = schemaBuilder.Build();
    
        if (!isBuildSuccess)
        {
          IReadOnlyList<string> errors = schemaBuilder.ErrorMessages;
          // Iterate and handle errors 
        }
      }
    }
    Creating table with subtypes
    {
      // Must be called within QueuedTask.Run
      void CreateTableWithSubtypes(SchemaBuilder schemaBuilder)
      {
        // Creating a 'Building' table with the subtype field 'BuildingType'
        FieldDescription buildingType = new FieldDescription("BuildingType", FieldType.Integer);
        FieldDescription buildingName = new FieldDescription("Name", FieldType.String);
    
        TableDescription tableDescription = new TableDescription("Building", new List<FieldDescription> { buildingName, buildingType });
    
        // Add the building type subtype with three subtypes - Business, Marketing, Security
        tableDescription.SubtypeFieldDescription = new SubtypeFieldDescription(buildingType.Name,
          new Dictionary<int, string> { { 1, "Business" }, { 2, "Marketing" }, { 3, "Security" } })
        {
          DefaultSubtypeCode = 3 // Assigning 'Security' building type as the default subtype
        };
    
        schemaBuilder.Create(tableDescription);
        schemaBuilder.Build();
      }
    }
    Creating relationship class
    {
      // Must be called within QueuedTask.Run
      void CreateRelationshipWithRelationshipRules(SchemaBuilder schemaBuilder)
      {
        // Creating a 'BuildingType' table with two fields - BuildingType and BuildingTypeDescription
        FieldDescription buildingType = FieldDescription.CreateIntegerField("BuildingType");
        FieldDescription buildingTypeeDescription = FieldDescription.CreateStringField("BuildingTypeDescription", 100);
        TableDescription buildingTypeDescription = new TableDescription("BuildingType",
          new List<FieldDescription>() { buildingType, buildingTypeeDescription });
        TableToken buildingtypeToken = schemaBuilder.Create(buildingTypeDescription);
    
        // Creating a 'Building' feature class with three fields - BuildingId, Address, and BuildingType
        FieldDescription buildingId = FieldDescription.CreateIntegerField("BuildingId");
        FieldDescription buildingAddress = FieldDescription.CreateStringField("Address", 100);
        FieldDescription usageSubType = FieldDescription.CreateIntegerField("UsageSubtype");
        FeatureClassDescription featureClassDescription = new FeatureClassDescription("Building",
          new List<FieldDescription> { buildingId, buildingAddress, buildingType, usageSubType },
          new ShapeDescription(GeometryType.Polygon, SpatialReferences.WGS84));
    
        // Set subtype details (optional)
        featureClassDescription.SubtypeFieldDescription = new SubtypeFieldDescription(usageSubType.Name,
          new Dictionary<int, string> { { 1, "Marketing" }, { 2, "Utility" } });
    
        FeatureClassToken buildingToken = schemaBuilder.Create(featureClassDescription);
    
        // Creating a 1:M relationship between the 'Building' feature class and 'BuildingType' table
        RelationshipClassDescription relationshipClassDescription = new RelationshipClassDescription(
          "BuildingToBuildingType", new FeatureClassDescription(buildingToken), new TableDescription(buildingtypeToken),
          RelationshipCardinality.OneToMany, buildingType.Name, buildingType.Name)
        {
          RelationshipType = RelationshipType.Composite
        };
    
        // Adding relationship rules for the 'Marketing' subtype
        relationshipClassDescription.RelationshipRuleDescriptions.Add(new RelationshipRuleDescription(1, null));
    
        schemaBuilder.Create(relationshipClassDescription);
        schemaBuilder.Build();
      }
    }
    Creating attributed relationship class
    {
      // Must be called within QueuedTask.Run
      void CreateAttributedRelationship(SchemaBuilder schemaBuilder)
      {
        // Creating a 'BuildingType' table with two fields - BuildingType and BuildingTypeDescription
        FieldDescription buildingType = FieldDescription.CreateIntegerField("BuildingType");
        FieldDescription buildingTypeeDescription = FieldDescription.CreateStringField("BuildingTypeDescription", 100);
        TableDescription buildingTypeDescription = new TableDescription("BuildingType",
          new List<FieldDescription>() { buildingType, buildingTypeeDescription });
        TableToken buildingtypeToken = schemaBuilder.Create(buildingTypeDescription);
    
        // Creating a 'Building' feature class with three fields - BuildingId, Address, and BuildingType
        FieldDescription buildingId = FieldDescription.CreateIntegerField("BuildingId");
        FieldDescription buildingAddress = FieldDescription.CreateStringField("Address", 100);
        FeatureClassDescription featureClassDescription = new FeatureClassDescription("Building",
          new List<FieldDescription> { buildingId, buildingAddress, buildingType },
          new ShapeDescription(GeometryType.Polygon, SpatialReferences.WGS84));
        FeatureClassToken buildingToken = schemaBuilder.Create(featureClassDescription);
    
        // Creating M:M relationship between the 'Building' feature class and 'BuildingType' table
        AttributedRelationshipClassDescription attributedRelationshipClassDescription =
          new AttributedRelationshipClassDescription("BuildingToBuildingType",
            new FeatureClassDescription(buildingToken),
            new TableDescription(buildingtypeToken), RelationshipCardinality.ManyToMany, "OBJECTID", "BuildingID",
            "OBJECTID", "BuildingTypeID");
    
        // Adding optional attribute field in the intermediate table - 'OwnershipPercentage' field
        attributedRelationshipClassDescription.FieldDescriptions.Add(FieldDescription.CreateIntegerField("OwnershipPercentage"));
    
        schemaBuilder.Create(attributedRelationshipClassDescription);
        schemaBuilder.Build();
      }
    }
    Create Entity and Relationship Types with SchemaBuilder
    {
            await QueuedTask.Run(() =>
    {
      using (var kg = GetKnowledgeGraph(url))
      {
        var entity_name = "PhoneCall";
        var relate_name = "WhoCalledWho";
    
        //Entity Fields
        var descs1 =
            new List<KnowledgeGraphPropertyDescription>();
        descs1.Add(
          new KnowledgeGraphPropertyDescription("PhoneOwner", FieldType.String));
        descs1.Add(
          new KnowledgeGraphPropertyDescription("PhoneNumber", FieldType.String));
        descs1.Add(
          new KnowledgeGraphPropertyDescription("LocationID", FieldType.BigInteger));
        descs1.Add(
          new KnowledgeGraphPropertyDescription("DateAndTime", FieldType.Date));
    
        //Relate Fields
        var descs2 =
            new List<KnowledgeGraphPropertyDescription>();
        descs2.Add(
          new KnowledgeGraphPropertyDescription("Foo", FieldType.String));
        descs2.Add(
          new KnowledgeGraphPropertyDescription("Bar", FieldType.String));
    
    
        var includeShape = true;//change to false to omit the shape column
        var hasZ = false;
        var hasM = false;
    
        KnowledgeGraphEntityTypeDescription entityDesc = null;
        KnowledgeGraphRelationshipTypeDescription relateDesc = null;
        if (includeShape)
        {
          var sr = kg.GetSpatialReference();
          var shp_desc = new ShapeDescription(GeometryType.Point, sr)
          {
            HasM = hasM,
            HasZ = hasZ
          };
          entityDesc = new KnowledgeGraphEntityTypeDescription(
            entity_name, descs1, shp_desc);
          relateDesc = new KnowledgeGraphRelationshipTypeDescription(
            relate_name, descs2, shp_desc);
        }
        else
        {
          entityDesc = new KnowledgeGraphEntityTypeDescription(
            entity_name, descs1);
          relateDesc = new KnowledgeGraphRelationshipTypeDescription(
            relate_name, descs2);
        }
        //Run the schema builder
        try
        {
          SchemaBuilder sb = new(kg);
          sb.Create(entityDesc);
          sb.Create(relateDesc);
          //Use the KnowledgeGraph extension method 'ApplySchemaEdits(...)'
          //to refresh the Pro UI
          if (!kg.ApplySchemaEdits(sb))
          {
            var err_msg = string.Join(",", sb.ErrorMessages.ToArray());
            System.Diagnostics.Debug.WriteLine($"Entity/Relate Create error: {err_msg}");
          }
        }
        catch (Exception ex)
        {
          System.Diagnostics.Debug.WriteLine(ex.ToString());
        }
      }
    });
          }
    Requirements

    Target Platforms: Windows 11 Home, Pro, Enterprise (64 bit)

    ArcGIS Pro version: 3.4 or higher.
    See Also