public void SetDefaultValue( 
   object defaultValue,
   Nullable<int> subtypeCode
)

private void ModifyExistingField(SchemaBuilder schemaBuilder, TableDefinition tableDefinition, string fieldNameToBeModified = "PropertyAddress")
{
  Field field = tableDefinition.GetFields().FirstOrDefault(f => f.Name.Contains(fieldNameToBeModified));

  // Update field's alias name and length
  FieldDescription fieldDescription = new FieldDescription(field)
  {
    AliasName = "Physical Property Address",
    Length = 50
  };

  // Update the default value
  fieldDescription.SetDefaultValue("123 Main St");
  
  // Enqueue modify operation
  schemaBuilder.Modify(new TableDescription(tableDefinition), field.Name, fieldDescription);
  
  // Execute DDL
  schemaBuilder.Build();
}