/// <summary>
        /// Retrieves list of Nodes with UniDirectional relationships
        /// </summary>
        /// <returns> List of Nodes from database</returns>
        public List <Node> GetNodes()
        {
            var adapter = new GraphTableAdapters.NodesTableAdapter();

            Graph.NodesDataTable nodesBack = adapter.GetData();
            IEnumerable <Node>   nodesList = nodesBack.Select(nodeBack => new Node
            {
                id            = (byte)nodeBack.id, //TODO change in Node to long cause contract failure
                label         = nodeBack.label,
                adjacentNodes = nodeBack.adjacentNodes
            });

            return(nodesList.ToList());
        }