示例#1
0
        /// <summary>
        /// Writes an DBObject into log
        /// </summary>
        /// <param name="myObjectUUID">The UUID of the Object</param>
        /// <param name="myTypeManager">The corresponding type manager</param>
        /// <param name="myTypeAttribute">The type attribute</param>
        public static void ShowDBObject(ObjectUUID myObjectUUID, DBTypeManager myTypeManager, TypeAttribute myTypeAttribute, DBObjectCache myObjectCache)
        {
            var currentDBObject = myObjectCache.LoadDBObjectStream(myTypeAttribute.GetRelatedType(myTypeManager), myObjectUUID);

            if (currentDBObject.Failed())
                throw new NotImplementedException();
        }
示例#2
0
        private Exceptional<Boolean> GetComplexMatch(IEnumerable<Tuple<GraphDBType, AAttributeIndex>> myIDX, Dictionary<DBObjectStream, AOperationDefinition> operands, DBObjectCache dbObjectCache, IDChainDefinition primIDNode, IDChainDefinition operandIDNode, DBContext dbContext, TypesOfAssociativity associativity, ref IExpressionGraph resultGraph, SessionSettings mySessionToken)
        {
            LevelKey primLevelKey = CreateLevelKey(primIDNode, dbContext.DBTypeManager);
            LevelKey operandLevelKey = CreateLevelKey(operandIDNode, dbContext.DBTypeManager);

            foreach (var aIDX in myIDX)
            {
                if (aIDX.Item2.IsUUIDIndex)
                {
                    #region UUID idx

                    var currentIndexRelatedType = dbContext.DBTypeManager.GetTypeByUUID(aIDX.Item2.IndexRelatedTypeUUID);

                    foreach (var aOperand in operands)
                    {

                        foreach (var _ObjectUUIDs in ((UUIDIndex)aIDX.Item2).GetAllUUIDs(currentIndexRelatedType, dbContext))
                        {
                            var DBObjectStream = dbObjectCache.LoadDBObjectStream(aIDX.Item1, _ObjectUUIDs);
                            if (DBObjectStream.Failed())
                            {
                                return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
                            }

                            if (IsValidDBObjectStreamForBinExpr(DBObjectStream.Value, primIDNode.LastAttribute, dbContext.DBTypeManager))
                            {
                                var aCtype = GraphDBTypeMapper.ConvertGraph2CSharp(primIDNode.LastAttribute.GetDBType(dbContext.DBTypeManager).Name);
                                IObject dbos = GetDbos(primIDNode, DBObjectStream.Value, dbContext, mySessionToken, dbObjectCache);

                                Exceptional<AOperationDefinition> tempResult;
                                if (aCtype == BasicType.SetOfDBObjects)
                                {
                                    tempResult = this.SimpleOperation(new TupleDefinition(aCtype, dbos, primIDNode.LastAttribute.GetDBType(dbContext.DBTypeManager)), aOperand.Value, TypesOfBinaryExpression.Complex);
                                }
                                else
                                {
                                    tempResult = this.SimpleOperation(new ValueDefinition(aCtype, dbos), aOperand.Value, TypesOfBinaryExpression.Complex);

                                }

                                if (tempResult.Failed())
                                    return new Exceptional<bool>(tempResult);

                                var tempOperatorResult = ((ValueDefinition)tempResult.Value);

                                if ((Boolean)tempOperatorResult.Value.Value)
                                {
                                    switch (associativity)
                                    {
                                        case TypesOfAssociativity.Neutral:
                                        case TypesOfAssociativity.Left:

                                            IntegrateInGraph(aOperand.Key, resultGraph, operandLevelKey, dbContext, dbObjectCache);

                                            break;
                                        case TypesOfAssociativity.Right:

                                            IntegrateInGraph(DBObjectStream.Value, resultGraph, primLevelKey, dbContext, dbObjectCache);

                                            break;
                                        default:

                                            return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
                                    }
                                }
                            }
                        }
                    }

                    #endregion
                }
                else
                {
                    return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
                }
            }

            return new Exceptional<bool>(true);
        }
示例#3
0
        private Exceptional<Boolean> MatchComplexData(TypesOfAssociativity associativity, DataContainer data, DBContext dbContext, DBObjectCache dbObjectCache, TypesOfBinaryExpression typeOfBinExpr, IEnumerable<Tuple<GraphDBType, AAttributeIndex>> leftIndices, IEnumerable<Tuple<GraphDBType, AAttributeIndex>> rightIndices, ref List<GraphDBError> errors, ref IExpressionGraph result, SessionSettings mySessionToken)
        {
            #region data

            Dictionary<DBObjectStream, AOperationDefinition> operandsLeft = null;
            Dictionary<DBObjectStream, AOperationDefinition> operandsRight = null;

            #endregion

            #region handle extraordinaries

            if (data.Extraordinaries.Item1 != null)
            {
                #region left extraordinary
                //there is something like a function or so

                operandsLeft = new Dictionary<DBObjectStream, AOperationDefinition>();

                //we have to calculate the real operand.
                //TODO: try to use attribute idx instead of uuid idx

                foreach (var aLeftIDX in leftIndices)
                {
                    AAttributeIndex currentLeftIdx = null;

                    #region get UUID idx
                    if (!(aLeftIDX.Item2.IsUUIDIndex))
                    {
                        currentLeftIdx = aLeftIDX.Item1.GetUUIDIndex(dbContext);
                    }
                    else
                    {
                        currentLeftIdx = aLeftIDX.Item2;
                    }

                    #endregion

                    var currentIndexRelatedType = dbContext.DBTypeManager.GetTypeByUUID(currentLeftIdx.IndexRelatedTypeUUID);

                    foreach (var aObjectUUIDs_Left in currentLeftIdx.GetAllValues(currentIndexRelatedType, dbContext))
                    {
                        foreach (var aObjectUUID_Left in aObjectUUIDs_Left)
                        {
                            var leftDBObject = dbObjectCache.LoadDBObjectStream(aLeftIDX.Item1, aObjectUUID_Left);
                            if (leftDBObject.Failed())
                            {
                                throw new NotImplementedException();
                            }

                            if (IsValidDBObjectStreamForBinExpr(leftDBObject.Value, data.IDChainDefinitions.Item1.LastAttribute, dbContext.DBTypeManager))
                            {
                                var oper = GetOperand(data.IDChainDefinitions.Item1, data.Extraordinaries.Item1, dbContext, leftDBObject.Value, dbObjectCache, mySessionToken);
                                if (oper.Failed())
                                    return new Exceptional<bool>(oper);

                                if (oper != null)
                                {
                                    operandsLeft.Add(leftDBObject.Value, oper.Value);
                                }
                            }
                        }
                    }
                }

                //from now on the binary expression is right complex, because there are atom values on the left
                typeOfBinExpr = TypesOfBinaryExpression.RightComplex;

                #endregion
            }

            if (data.Extraordinaries.Item2 != null)
            {
                #region right extraordinary
                //there is something like a function or so
                operandsRight = new Dictionary<DBObjectStream, AOperationDefinition>();

                foreach (var aRightIDX in rightIndices)
                {
                    AAttributeIndex currentRightIdx = null;

                    #region get UUID idx
                    //we have to calculate the real operand.
                    //TODO: try to use attribute idx instead of uuid idx

                    if (!(aRightIDX.Item2.IsUUIDIndex))
                    {
                        currentRightIdx = aRightIDX.Item1.GetUUIDIndex(dbContext);
                    }
                    else
                    {
                        currentRightIdx = aRightIDX.Item2;
                    }

                    #endregion

                    var currentIndexRelatedType = dbContext.DBTypeManager.GetTypeByUUID(currentRightIdx.IndexRelatedTypeUUID);

                    foreach (var aObjectUUIDs_Right in currentRightIdx.GetAllValues(currentIndexRelatedType, dbContext))
                    {
                        foreach (var aObjectUUID_Right in aObjectUUIDs_Right)
                        {
                            var rightDBObject = dbObjectCache.LoadDBObjectStream(aRightIDX.Item1, aObjectUUID_Right);
                            if (rightDBObject.Failed())
                            {
                                throw new NotImplementedException();
                            }

                            if (IsValidDBObjectStreamForBinExpr(rightDBObject.Value, data.IDChainDefinitions.Item2.LastAttribute, dbContext.DBTypeManager))
                            {
                                var oper = GetOperand(data.IDChainDefinitions.Item2, data.Extraordinaries.Item2, dbContext, rightDBObject.Value, dbObjectCache, mySessionToken);
                                if (oper.Failed())
                                    return new Exceptional<bool>(oper);

                                if (oper != null)
                                {
                                    operandsRight.Add(rightDBObject.Value, oper.Value);
                                }
                            }
                        }
                    }
                }

                if (typeOfBinExpr == TypesOfBinaryExpression.RightComplex)
                {
                    typeOfBinExpr = TypesOfBinaryExpression.Atom;
                }

                #endregion
            }

            #endregion

            switch (typeOfBinExpr)
            {
                case TypesOfBinaryExpression.Atom:

                    #region atom

                    switch (associativity)
                    {
                        case TypesOfAssociativity.Unknown:
                        case TypesOfAssociativity.Neutral:
                            GetComplexAtom(dbContext, operandsLeft, operandsRight, data.IDChainDefinitions.Item1, dbObjectCache, ref result);
                            GetComplexAtom(dbContext, operandsRight, operandsLeft, data.IDChainDefinitions.Item2, dbObjectCache, ref result);
                            break;

                        case TypesOfAssociativity.Left:

                            GetComplexAtom(dbContext, operandsLeft, operandsRight, data.IDChainDefinitions.Item1, dbObjectCache, ref result);

                            break;
                        case TypesOfAssociativity.Right:

                            GetComplexAtom(dbContext, operandsRight, operandsLeft, data.IDChainDefinitions.Item2, dbObjectCache, ref result);

                            break;

                        default:
                            return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
                    }

                    #endregion

                    break;
                case TypesOfBinaryExpression.LeftComplex:

                    #region Left complex

                    GetComplexMatch(leftIndices, operandsRight, dbObjectCache, data.IDChainDefinitions.Item1, data.IDChainDefinitions.Item2, dbContext, associativity, ref result, mySessionToken);

                    #endregion

                    break;
                case TypesOfBinaryExpression.RightComplex:

                    #region Right complex

                    GetComplexMatch(rightIndices, operandsLeft, dbObjectCache, data.IDChainDefinitions.Item2, data.IDChainDefinitions.Item1, dbContext, associativity, ref result, mySessionToken);

                    #endregion

                    break;
                case TypesOfBinaryExpression.Complex:

                    #region Complex

                    LevelKey leftLevelKey = CreateLevelKey(data.IDChainDefinitions.Item1, dbContext.DBTypeManager);
                    LevelKey rightLevelKey = CreateLevelKey(data.IDChainDefinitions.Item2, dbContext.DBTypeManager);
                    GraphDBType leftGraphDBType = data.IDChainDefinitions.Item1.LastType;
                    GraphDBType rightGraphDBType = data.IDChainDefinitions.Item2.LastType;

                    #region exception

                    if (leftIndices.CountIsGreater(1) || rightIndices.CountIsGreater(1))
                    {
                        return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
                    }

                    #endregion

                    var leftIndexRelatedType = dbContext.DBTypeManager.GetTypeByUUID(leftIndices.First().Item2.IndexRelatedTypeUUID);
                    var rightIndexRelatedType = dbContext.DBTypeManager.GetTypeByUUID(rightIndices.First().Item2.IndexRelatedTypeUUID);

                    foreach (var ObjectUUIDs_left in leftIndices.First().Item2.GetAllValues(leftIndexRelatedType, dbContext))
                    {
                        foreach (var aLeftUUID in ObjectUUIDs_left)
                        {
                            var leftDBObject = dbObjectCache.LoadDBObjectStream(leftIndices.First().Item1, aLeftUUID);
                            if (leftDBObject.Failed())
                            {
                                return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
                            }

                            if (IsValidDBObjectStreamForBinExpr(leftDBObject.Value, data.IDChainDefinitions.Item1.LastAttribute, dbContext.DBTypeManager))
                            {

                                foreach (var ObjectUUIDs_right in rightIndices.First().Item2.GetAllValues(rightIndexRelatedType, dbContext))
                                {
                                    foreach (var aRightUUID in ObjectUUIDs_right)
                                    {

                                        var rightDBObject = dbObjectCache.LoadDBObjectStream(rightIndices.First().Item1, aRightUUID);
                                        if (rightDBObject.Failed())
                                        {
                                            return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
                                        }

                                        if (IsValidDBObjectStreamForBinExpr(rightDBObject.Value, data.IDChainDefinitions.Item2.LastAttribute, dbContext.DBTypeManager))
                                        {
                                            //everything is valid

                                            var leftType = GraphDBTypeMapper.ConvertGraph2CSharp(data.IDChainDefinitions.Item1.LastAttribute.GetDBType(dbContext.DBTypeManager).Name);
                                            var rightType = GraphDBTypeMapper.ConvertGraph2CSharp(data.IDChainDefinitions.Item2.LastAttribute.GetDBType(dbContext.DBTypeManager).Name);

                                            AOperationDefinition leftValue;
                                            AOperationDefinition rightValue;

                                            if (data.IDChainDefinitions.Item1.LastAttribute.KindOfType == KindsOfType.SetOfReferences
                                                || data.IDChainDefinitions.Item1.LastAttribute.KindOfType == KindsOfType.ListOfNoneReferences || data.IDChainDefinitions.Item1.LastAttribute.KindOfType == KindsOfType.SetOfNoneReferences)
                                                leftValue = new TupleDefinition(leftType, leftDBObject.Value.GetAttribute(data.IDChainDefinitions.Item1.LastAttribute.UUID), data.IDChainDefinitions.Item1.LastAttribute.GetDBType(dbContext.DBTypeManager));
                                            else
                                                leftValue = new ValueDefinition(leftType, leftDBObject.Value.GetAttribute(data.IDChainDefinitions.Item1.LastAttribute.UUID, data.IDChainDefinitions.Item1.LastAttribute.GetRelatedType(dbContext.DBTypeManager), dbContext));

                                            if (data.IDChainDefinitions.Item2.LastAttribute.KindOfType == KindsOfType.SetOfReferences
                                                || data.IDChainDefinitions.Item2.LastAttribute.KindOfType == KindsOfType.ListOfNoneReferences || data.IDChainDefinitions.Item2.LastAttribute.KindOfType == KindsOfType.SetOfNoneReferences)
                                                rightValue = new TupleDefinition(rightType, rightDBObject.Value.GetAttribute(data.IDChainDefinitions.Item2.LastAttribute.UUID), data.IDChainDefinitions.Item2.LastAttribute.GetDBType(dbContext.DBTypeManager));
                                            else
                                                rightValue = new ValueDefinition(rightType, rightDBObject.Value.GetAttribute(data.IDChainDefinitions.Item2.LastAttribute.UUID, data.IDChainDefinitions.Item2.LastAttribute.GetRelatedType(dbContext.DBTypeManager), dbContext));

                                            var tempSimpleOperationResult = this.SimpleOperation(leftValue, rightValue, typeOfBinExpr);
                                            if (tempSimpleOperationResult.Failed())
                                                return new Exceptional<bool>(tempSimpleOperationResult);

                                            var tempOperatorResult = tempSimpleOperationResult.Value;

                                            if ((Boolean)(tempOperatorResult as ValueDefinition).Value.Value)
                                            {
                                                //found sth that is really true

                                                #region insert into graph

                                                switch (associativity)
                                                {
                                                    case TypesOfAssociativity.Neutral:
                                                    case TypesOfAssociativity.Left:

                                                        IntegrateInGraph(leftDBObject.Value, result, leftLevelKey, dbContext, dbObjectCache);

                                                        break;
                                                    case TypesOfAssociativity.Right:

                                                        IntegrateInGraph(rightDBObject.Value, result, rightLevelKey, dbContext, dbObjectCache);

                                                        break;
                                                    case TypesOfAssociativity.Unknown:

                                                        if (Type == TypesOfOperators.AffectsLowerLevels)
                                                        {
                                                            result.AddNodesWithComplexRelation(leftDBObject, leftLevelKey, rightDBObject, rightLevelKey, dbObjectCache, 1);
                                                        }
                                                        else
                                                        {
                                                            result.AddNodesWithComplexRelation(leftDBObject, leftLevelKey, rightDBObject, rightLevelKey, dbObjectCache, 0);
                                                        }

                                                        break;
                                                    default:

                                                        return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
                                                }

                                                #endregion
                                            }
                                        }
                                    }
                                }

                                #region clean lower levels

                                if (Type == TypesOfOperators.AffectsLowerLevels)
                                {
                                    switch (associativity)
                                    {
                                        case TypesOfAssociativity.Neutral:
                                        case TypesOfAssociativity.Left:

                                            CleanLowerLevel(leftLevelKey, dbContext, dbObjectCache, result);

                                            break;
                                        case TypesOfAssociativity.Right:

                                            CleanLowerLevel(rightLevelKey, dbContext, dbObjectCache, result);

                                            break;
                                        case TypesOfAssociativity.Unknown:

                                            CleanLowerLevel(leftLevelKey, dbContext, dbObjectCache, result);
                                            CleanLowerLevel(rightLevelKey, dbContext, dbObjectCache, result);

                                            break;
                                        default:

                                            return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
                                    }
                                }

                                #endregion
                            }
                        }
                    }

                    #endregion

                    break;
                default:

                    return new Exceptional<bool>(new Error_NotImplemented(new System.Diagnostics.StackTrace(true)));
            }

            return new Exceptional<bool>(true);
        }
示例#4
0
        /// <summary>
        /// This method returns the DBObjectStream that is referenced by this node.
        /// </summary>
        /// <param name="myDBObjectCache">The actual query cache.</param>
        /// <param name="myTypeUUID">The TypeUUID of the DBObject.</param>
        /// <returns>A DBObjectStream</returns>
        public DBObjectStream GetDBObjectStream(DBObjectCache myDBObjectCache, TypeUUID myTypeUUID)
        {
            lock (_ObjectUUID)
            {
                if (_Object != null)
                {
                    return _Object;
                }
                else
                {

                    var tempObject = myDBObjectCache.LoadDBObjectStream(myTypeUUID, GetObjectUUID());
                    if (tempObject.Failed())
                    {
                        return null;
                    }

                    _Object = tempObject.Value;

                    return _Object;
                }
            }
        }
示例#5
0
        /// <summary>
        /// Writes all paths included in the HashSet. Every object is represented via a given attribute.
        /// 
        /// example path between fry and morbo (attribute is "Name") 
        /// 
        /// output:
        /// Fry -> Leela -> Lrrr -> Morbo
        /// </summary>
        /// <param name="myPaths">An HashSet which contains Lists of UUIDs</param>
        /// <param name="myTypeManager">The type manager to load the DBObjects</param>
        /// <param name="myTypeAttribute">The Type Attribute</param>
        /// <param name="myAttribute">The Attribute which shall be used for output.</param>
        public static void ShowDBObjects(HashSet<List<ObjectUUID>> myPaths, DBTypeManager myTypeManager, TypeAttribute myTypeAttribute, String myAttribute, DBObjectCache myObjectCache)
        {
            var attributeUUID = myTypeAttribute.GetRelatedType(myTypeManager).GetTypeSpecificAttributeByName(myAttribute).UUID;

            foreach (var path in myPaths)
            {

                var pathString = new StringBuilder();
                Exceptional<DBObjectStream> currentDBObject;

                foreach (var _ObjectUUID in path)
                {
                    //load from DB
                    currentDBObject = myObjectCache.LoadDBObjectStream(myTypeAttribute.GetRelatedType(myTypeManager), _ObjectUUID);
                    if (currentDBObject.Failed())
                    {
                        throw new NotImplementedException();
                    }

                    pathString.Append(currentDBObject.Value.GetAttribute(attributeUUID) + " -> ");
                }

                ////_Logger.Info(pathString.ToString());
                pathString.Remove(0, pathString.Length);

            }
        }
示例#6
0
        /// <summary>
        /// Searches shortest, all shortest or all paths starting from "myStart" to "myEnd".
        /// </summary>
        /// <param name="myTypeAttribute">The Attribute representing the edge to follow (p.e. "Friends")</param>
        /// <param name="myTypeManager">The TypeManager for the Node type</param>
        /// <param name="myDBObjectCache">The Object Cache for faster object lookup</param>
        /// <param name="myStart">The start node</param>
        /// <param name="myEnd">The end node</param>
        /// <param name="shortestOnly">true, if only shortest path shall be found</param>
        /// <param name="findAll">if true and shortestOnly is true, all shortest paths will be found. if true, and shortest only is false, all paths will be searched</param>
        /// <param name="myMaxDepth">The maximum depth to search</param>
        /// <param name="myMaxPathLength">The maximum path length which shall be analyzed</param>
        /// <returns>A HashSet which contains all found paths. Every path is represented by a List of ObjectUUIDs</returns>
        public HashSet<List<ObjectUUID>> Find(TypeAttribute myTypeAttribute, DBTypeManager myTypeManager, DBObjectCache myDBObjectCache, DBObjectStream myStart, DBObjectStream myEnd, bool shortestOnly, bool findAll, byte myMaxDepth, byte myMaxPathLength)
        {
            #region data

            //queue for BFS
            Queue<Node> queue = new Queue<Node>();

            //Dictionary to store visited TreeNodes
            BigDictionary<ObjectUUID, Node> visitedNodes = new BigDictionary<ObjectUUID, Node>();

            //current depth
            byte depth = 0;

            //first node in path tree, the start of the select
            Node root = new Node(myStart.ObjectUUID);

            //root changed in Dictionary because of BidirectionalBFS
            HashSet<ObjectUUID> rootFriends = new HashSet<ObjectUUID>();

            //target node, the target of the select
            Node target = new Node(myEnd.ObjectUUID);

            //holds the key of the backwardedge
            EdgeKey edgeKey = new EdgeKey(myTypeAttribute);

            //dummy node to check in which level the BFS is
            Node dummy = new Node();

            //if the maxDepth is greater then maxPathLength, then set maxDepth to maxPathLength
            if (myMaxDepth > myMaxPathLength)
            {
                myMaxDepth = myMaxPathLength;
            }

            //enqueue first node to start the BFS
            queue.Enqueue(root);
            queue.Enqueue(dummy);

            //add root to visitedNodes
            visitedNodes.Add(root.Key, root);

            //holds the actual DBObject
            Exceptional<DBObjectStream> currentDBObject;

            #endregion

            #region BFS

            //Log start
            ////_Logger.Info("Starting BFS..");

            //check if root node has edge and target has backwardedge
            var dbObject = myDBObjectCache.LoadDBObjectStream(myTypeAttribute.GetRelatedType(myTypeManager), root.Key);
            if (dbObject.Failed())
            {
                throw new NotImplementedException();
            }

            if (!dbObject.Value.HasAttribute(myTypeAttribute.UUID, myTypeAttribute.GetRelatedType(myTypeManager)))
            {
                ////_Logger.Info("Abort search! Start object has no edge!");
                //Console.WriteLine("No paths found!");
                return null;
            }

            var be = myDBObjectCache.LoadDBBackwardEdgeStream(myTypeAttribute.GetRelatedType(myTypeManager), target.Key);
            if (be.Failed())
            {
                throw new NotImplementedException();
            }

            if (!be.Value.ContainsBackwardEdge(edgeKey))
            {
                ////_Logger.Info("Abort search! End object has no backwardedge!");
                //Console.WriteLine("No paths found!");
                return null;
            }

            //if there is more than one object in the queue and the actual depth is less than MaxDepth
            while ((queue.Count > 0) && (depth <= myMaxDepth))
            {
                //get the first Object of the queue
                Node current = queue.Dequeue();

                //dummy
                if (current.Key == null)
                {
                    break;
                }

                //load DBObject
                currentDBObject = myDBObjectCache.LoadDBObjectStream(myTypeAttribute.GetRelatedType(myTypeManager), current.Key);
                if (currentDBObject.Failed())
                {
                    throw new NotImplementedException();
                }

                if (currentDBObject.Value.HasAttribute(myTypeAttribute.UUID, myTypeAttribute.GetRelatedType(myTypeManager)))
                {
                    if (myTypeAttribute.EdgeType is ASetOfReferencesEdgeType)
                    {
                        //get all referenced ObjectUUIDs using the given Edge
                        var objectUUIDs = (currentDBObject.Value.GetAttribute(myTypeAttribute.UUID) as ASetOfReferencesEdgeType).GetAllReferenceIDs();
                        Node currentNode;

                        foreach(ObjectUUID dbo in objectUUIDs)
                        {
                            //only for debug
                            //var currentNodeObject = myTypeManager.LoadDBObject(myTypeAttribute.RelatedGraphType, dbo);

                            //create a new node and set current = parent, currentNode = child
                            currentNode = new Node(dbo, current);

                            //if the child is the target
                            if (currentNode.Key.Equals(myEnd.ObjectUUID))
                            {
                                //node points on the target
                                target.Parents.Add(current);

                                //if shortestOnly == true we are finished here
                                if(shortestOnly)
                                {
                                    if (findAll)
                                    {
                                        //continue searching the current depth if there are any other shortest paths
                                        myMaxDepth = Convert.ToByte(depth);
                                        myMaxPathLength = Convert.ToByte(depth + 2);
                                    }
                                    else
                                    {
                                        ////_Logger.Info("found shortest path.");
                                        //got the shortest, finished
                                        return new TargetAnalyzer(root, rootFriends, target, myMaxPathLength, shortestOnly, findAll).getPaths();
                                    }
                                }
                            }
                            else
                            {
                                //been there before
                                if (visitedNodes.ContainsKey(currentNode.Key))
                                {
                                    //if currentNode.Key isn't root set parent
                                    if (!rootFriends.Contains(currentNode.Key))
                                    {
                                        //node has more then one parent
                                        visitedNodes[currentNode.Key].Parents.Add(current);
                                    }
                                    continue;
                                }

                                //never seen before
                                //mark the node as visited
                                visitedNodes.Add(currentNode.Key, currentNode);
                                //and look what comes on the next level of depth
                                queue.Enqueue(currentNode);

                                //some logging
                                if (queue.Count % 10000 == 0)
                                {
                                    ////_Logger.Info(queue.Count + " elements enqueued..");
                                }
                            }
                        }
                    }
                    else if (myTypeAttribute.EdgeType is ASingleReferenceEdgeType)
                    {
                        throw new NotImplementedException();
                    }
                    else
                    {
                        throw new NotImplementedException();
                    }
                }

                //if a new depth is reached
                if (queue.First() == dummy)
                {
                    //enqueue the dummy at the end of to mark the next depth
                    queue.Enqueue(queue.Dequeue());
                    //one step deeper in the dungen
                    depth++;
                    ////_Logger.Info("going deeper in the dungeon.. current level: " + depth);
                }
            }

            #endregion

            ////_Logger.Info("finished building path-graph.. starting analyzer");
            //analyze paths
            return new TargetAnalyzer(root, rootFriends, target, myMaxPathLength, shortestOnly, findAll).getPaths();
        }