private void DoWrite <T>(T entity, bool isNew) where T : BaseTableEntity
        {
            var context = new OperationContext();
            var fields  = entity.WriteEntity(context);

            if (isNew)
            {
                _tableStore.StoreNew(_table, entity.PartitionKey, entity.RowKey, fields);
            }
            else
            {
                _tableStore.StoreExisting(_table, entity.PartitionKey, entity.RowKey, fields);
            }
        }