public void Create( 
   IndexDescription indexDescription
)

{
  // 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();
  }
}

{
  // 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 
    }
  }
}

{
  // 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();
  }
}

{
  // 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();
  }
}

{
  // 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();
  }
}

{
  await QueuedTask.Run(() =>
  {
    using (var kg = GetKnowledgeGraph(url))
    {
      var entity_name = "PhoneCall";

      //indexes are managed on the GDB objects...
      var entity_table_def = kg.GetDefinition<TableDefinition>(entity_name);
      var entity_table_desc = new TableDescription(entity_table_def);

      var entity_table_flds = entity_table_def.GetFields();
      AttributeIndexDescription attr_index1 = null;
      AttributeIndexDescription attr_index2 = null;
      foreach (var fld in entity_table_flds)
      {
        //index the first string field
        if (fld.FieldType == FieldType.String && attr_index1 == null)
        {
          if (fld.Name == "ESRI__ID")//special case
            continue;
          //Index _must_ be ascending for KG
          attr_index1 = new AttributeIndexDescription(
            "Index1", entity_table_desc, new List<string> { fld.Name })
          {
            IsAscending = true
          };
        }
        //index the first numeric field (if there is one)
        if ((fld.FieldType == FieldType.BigInteger ||
             fld.FieldType == FieldType.Integer ||
             fld.FieldType == FieldType.Single ||
             fld.FieldType == FieldType.SmallInteger ||
             fld.FieldType == FieldType.Double) && attr_index2 == null)
        {
          attr_index2 = new AttributeIndexDescription(
            "Index2", entity_table_desc, new List<string> { fld.Name })
          {
            IsAscending = true,
            IsUnique = true //optional - unique if all values are to be unique in the index
          };
        }
        if (attr_index1 != null && attr_index2 != null) break;
      }

      if (attr_index1 == null && attr_index2 == null)
        return; //nothing to index

      //Run the schema builder
      try
      {
        SchemaBuilder sb = new(kg);
        if (attr_index1 != null)
          sb.Create(attr_index1);
        if (attr_index2 != null)
          sb.Create(attr_index2);
        if (!kg.ApplySchemaEdits(sb))
        {
          var err_msg = string.Join(",", sb.ErrorMessages.ToArray());
          System.Diagnostics.Debug.WriteLine($"Create index error: {err_msg}");
        }
      }
      catch (Exception ex)
      {
        System.Diagnostics.Debug.WriteLine(ex.ToString());
      }
    }
  });
}