private void merge(ExtendedProperties repoExtendedProperties, ExtendedProperties columnExtendedProperties)
        {
            foreach (var extendedProperty in columnExtendedProperties.ToList())
            {
                if (repoExtendedProperties.Contains(extendedProperty.Name))
                {
                    continue;
                }

                repoExtendedProperties.Add(extendedProperty);
                columnExtendedProperties.Remove(extendedProperty.Name);
            }
        }