Esempio n. 1
0
        public static ExpressionNode CombineConditions(LogicalOperator logicalOperator, IList <ExpressionNode> conditions)
        {
            if (conditions == null || conditions.Count == 0)
            {
                return(null);
            }

            ExpressionBuilder expressionBuilder = new ExpressionBuilder();

            foreach (ExpressionNode condition in conditions)
            {
                if (condition != null)
                {
                    expressionBuilder.Push(condition);
                }
            }

            if (expressionBuilder.Count == 0)
            {
                return(null);
            }

            expressionBuilder.PushNAry(logicalOperator);
            return(expressionBuilder.Pop());
        }
Esempio n. 2
0
        private void SetWhenPassthru(ICollection <ExpressionNode> processedWhenExpressions)
        {
            if (processedWhenExpressions.Count == 0)
            {
                _currentPassthruPredicate = null;
            }
            else
            {
                foreach (ExpressionNode processedWhenExpression in processedWhenExpressions)
                {
                    ExpressionNode clonedExpr = (ExpressionNode)processedWhenExpression.Clone();
                    _expressionBuilder.Push(clonedExpr);
                }

                _expressionBuilder.PushNAry(LogicalOperator.Or);
                _currentPassthruPredicate = _expressionBuilder.Pop();
            }
        }
Esempio n. 3
0
		public static ExpressionNode CombineConditions(LogicalOperator logicalOperator, IList<ExpressionNode> conditions)
		{
			if (conditions == null || conditions.Count == 0)
				return null;

			ExpressionBuilder expressionBuilder = new ExpressionBuilder();
			foreach (ExpressionNode condition in conditions)
			{
				if (condition != null)
					expressionBuilder.Push(condition);
			}

			if (expressionBuilder.Count == 0)
				return null;

			expressionBuilder.PushNAry(logicalOperator);
			return expressionBuilder.Pop();
		}
Esempio n. 4
0
        public override ExpressionNode VisitAllAnySubselect(AllAnySubselect expression)
        {
            expression.Left = VisitExpression(expression.Left);
            ResultAlgebraNode algebrizedQuery = Algebrizer.Convert(expression.Query);

            ExpressionNode leftExpression = expression.Left;
            RowBufferEntryExpression rightExpression = new RowBufferEntryExpression();
            rightExpression.RowBufferEntry = algebrizedQuery.OutputList[0];

            ExpressionBuilder expressionBuilder = new ExpressionBuilder();
            expressionBuilder.Push(leftExpression);
            expressionBuilder.Push(rightExpression);
            expressionBuilder.PushBinary(expression.Op);

            bool negated = (expression.Type == AllAnySubselect.AllAnyType.All);
            if (negated)
            {
                expressionBuilder.PushUnary(UnaryOperator.LogicalNot);
                expressionBuilder.Push(leftExpression);
                expressionBuilder.PushIsNull();
                expressionBuilder.Push(rightExpression);
                expressionBuilder.PushIsNull();
                expressionBuilder.PushNAry(LogicalOperator.Or);
            }

            ExpressionNode filterPredicate = expressionBuilder.Pop();

            FilterAlgebraNode filterAlgebraNode = new FilterAlgebraNode();
            filterAlgebraNode.Input = algebrizedQuery;
            filterAlgebraNode.Predicate = filterPredicate;

            AlgebraNode input = GetAndResetLastNode();

            if (!negated && !ProbingEnabled && input == null)
            {
                SetLastAlgebraNode(filterAlgebraNode);
                return LiteralExpression.FromBoolean(true);
            }
            else
            {
                if (input == null)
                    input = CreateConstantScan();

                RowBufferEntry probeColumn = CreateProbeColumn();

                JoinAlgebraNode joinAlgebraNode = new JoinAlgebraNode();
                joinAlgebraNode.PassthruPredicate = CurrentPassthruPredicate;
                joinAlgebraNode.ProbeBufferEntry = probeColumn;
                joinAlgebraNode.Left = input;
                joinAlgebraNode.Right = filterAlgebraNode;
                joinAlgebraNode.Op = negated ? JoinAlgebraNode.JoinOperator.LeftAntiSemiJoin : JoinAlgebraNode.JoinOperator.LeftSemiJoin;

                SetLastAlgebraNode(joinAlgebraNode);
                return CreateProbeColumnRef(probeColumn);
            }
        }
Esempio n. 5
0
        public override QueryNode VisitBinaryQuery(BinaryQuery query)
        {
            switch (query.Op)
            {
            case BinaryQueryOperator.Intersect:
            case BinaryQueryOperator.Except:
            {
                ResultAlgebraNode left  = ((ResultAlgebraNode)ConvertAstNode(query.Left));
                ResultAlgebraNode right = ((ResultAlgebraNode)ConvertAstNode(query.Right));

                // Create distinct sort

                SortAlgebraNode sortAlgebraNode = new SortAlgebraNode();
                sortAlgebraNode.Distinct    = true;
                sortAlgebraNode.Input       = left;
                sortAlgebraNode.SortEntries = left.OutputList;
                sortAlgebraNode.SortOrders  = CreateAscendingSortOrders(sortAlgebraNode.SortEntries.Length);

                // Insert left (anti) semi join to (except) intersect left and right.

                ExpressionBuilder expressionBuilder = new ExpressionBuilder();
                for (int i = 0; i < left.OutputList.Length; i++)
                {
                    RowBufferEntryExpression leftExpr = new RowBufferEntryExpression();
                    leftExpr.RowBufferEntry = left.OutputList[i];

                    RowBufferEntryExpression rightExpr = new RowBufferEntryExpression();
                    rightExpr.RowBufferEntry = right.OutputList[i];

                    expressionBuilder.Push(leftExpr);
                    expressionBuilder.Push(rightExpr);
                    expressionBuilder.PushBinary(BinaryOperator.Equal);
                    expressionBuilder.Push(leftExpr);
                    expressionBuilder.PushIsNull();
                    expressionBuilder.Push(rightExpr);
                    expressionBuilder.PushIsNull();
                    expressionBuilder.PushBinary(BinaryOperator.LogicalAnd);
                    expressionBuilder.PushBinary(BinaryOperator.LogicalOr);
                }
                expressionBuilder.PushNAry(LogicalOperator.And);
                ExpressionNode joinCondition = expressionBuilder.Pop();

                JoinAlgebraNode joinAlgebraNode = new JoinAlgebraNode();
                if (query.Op == BinaryQueryOperator.Intersect)
                {
                    joinAlgebraNode.Op = JoinAlgebraNode.JoinOperator.LeftSemiJoin;
                }
                else
                {
                    joinAlgebraNode.Op = JoinAlgebraNode.JoinOperator.LeftAntiSemiJoin;
                }
                joinAlgebraNode.Left      = sortAlgebraNode;
                joinAlgebraNode.Right     = right;
                joinAlgebraNode.Predicate = joinCondition;
                SetLastAlgebraNode(joinAlgebraNode);

                ResultAlgebraNode resultAlgebraNode = new ResultAlgebraNode();
                resultAlgebraNode.Input       = GetLastAlgebraNode();
                resultAlgebraNode.OutputList  = left.OutputList;
                resultAlgebraNode.ColumnNames = left.ColumnNames;
                SetLastAlgebraNode(resultAlgebraNode);
                break;
            }

            case BinaryQueryOperator.Union:
            case BinaryQueryOperator.UnionAll:
            {
                // Build a flat list with all inputs.

                List <QueryNode> inputList = AstUtil.FlattenBinaryQuery(query);

                AlgebraNode[] inputs = new AlgebraNode[inputList.Count];
                for (int i = 0; i < inputs.Length; i++)
                {
                    inputs[i] = ConvertAstNode(inputList[i]);
                }

                int outputColumnCount = inputs[0].OutputList.Length;

                UnitedValueDefinition[] definedValues       = new UnitedValueDefinition[outputColumnCount];
                List <RowBufferEntry>   definedValueEntries = new List <RowBufferEntry>();

                for (int i = 0; i < outputColumnCount; i++)
                {
                    RowBufferEntry rowBufferEntry = new RowBufferEntry(inputs[0].OutputList[i].DataType);
                    definedValueEntries.Add(rowBufferEntry);

                    UnitedValueDefinition definedValue = new UnitedValueDefinition();
                    definedValue.Target = rowBufferEntry;

                    List <RowBufferEntry> dependencies = new List <RowBufferEntry>();
                    foreach (ResultAlgebraNode node in inputs)
                    {
                        dependencies.Add(node.OutputList[i]);
                    }
                    definedValue.DependendEntries = dependencies.ToArray();

                    definedValues[i] = definedValue;
                }

                ConcatAlgebraNode concatAlgebraNode = new ConcatAlgebraNode();
                concatAlgebraNode.Inputs        = inputs;
                concatAlgebraNode.DefinedValues = definedValues;
                SetLastAlgebraNode(concatAlgebraNode);

                if (query.Op == BinaryQueryOperator.Union)
                {
                    SortAlgebraNode sortAlgebraNode = new SortAlgebraNode();
                    sortAlgebraNode.Distinct    = true;
                    sortAlgebraNode.Input       = GetLastAlgebraNode();
                    sortAlgebraNode.SortEntries = definedValueEntries.ToArray();
                    sortAlgebraNode.SortOrders  = CreateAscendingSortOrders(sortAlgebraNode.SortEntries.Length);
                    SetLastAlgebraNode(sortAlgebraNode);
                }

                ResultAlgebraNode unionResultAlgebraNode = new ResultAlgebraNode();
                unionResultAlgebraNode.Input       = GetLastAlgebraNode();
                unionResultAlgebraNode.ColumnNames = ((ResultAlgebraNode)inputs[0]).ColumnNames;
                unionResultAlgebraNode.OutputList  = definedValueEntries.ToArray();
                SetLastAlgebraNode(unionResultAlgebraNode);

                break;
            }
            }

            return(query);
        }
Esempio n. 6
0
        public override ExpressionNode VisitAllAnySubselect(AllAnySubselect expression)
        {
            expression.Left = VisitExpression(expression.Left);
            ResultAlgebraNode algebrizedQuery = Algebrizer.Convert(expression.Query);

            ExpressionNode           leftExpression  = expression.Left;
            RowBufferEntryExpression rightExpression = new RowBufferEntryExpression();

            rightExpression.RowBufferEntry = algebrizedQuery.OutputList[0];

            ExpressionBuilder expressionBuilder = new ExpressionBuilder();

            expressionBuilder.Push(leftExpression);
            expressionBuilder.Push(rightExpression);
            expressionBuilder.PushBinary(expression.Op);

            bool negated = (expression.Type == AllAnySubselect.AllAnyType.All);

            if (negated)
            {
                expressionBuilder.PushUnary(UnaryOperator.LogicalNot);
                expressionBuilder.Push(leftExpression);
                expressionBuilder.PushIsNull();
                expressionBuilder.Push(rightExpression);
                expressionBuilder.PushIsNull();
                expressionBuilder.PushNAry(LogicalOperator.Or);
            }

            ExpressionNode filterPredicate = expressionBuilder.Pop();

            FilterAlgebraNode filterAlgebraNode = new FilterAlgebraNode();

            filterAlgebraNode.Input     = algebrizedQuery;
            filterAlgebraNode.Predicate = filterPredicate;

            AlgebraNode input = GetAndResetLastNode();

            if (!negated && !ProbingEnabled && input == null)
            {
                SetLastAlgebraNode(filterAlgebraNode);
                return(LiteralExpression.FromBoolean(true));
            }
            else
            {
                if (input == null)
                {
                    input = CreateConstantScan();
                }

                RowBufferEntry probeColumn = CreateProbeColumn();

                JoinAlgebraNode joinAlgebraNode = new JoinAlgebraNode();
                joinAlgebraNode.PassthruPredicate = CurrentPassthruPredicate;
                joinAlgebraNode.ProbeBufferEntry  = probeColumn;
                joinAlgebraNode.Left  = input;
                joinAlgebraNode.Right = filterAlgebraNode;
                joinAlgebraNode.Op    = negated ? JoinAlgebraNode.JoinOperator.LeftAntiSemiJoin : JoinAlgebraNode.JoinOperator.LeftSemiJoin;

                SetLastAlgebraNode(joinAlgebraNode);
                return(CreateProbeColumnRef(probeColumn));
            }
        }
        public override AlgebraNode VisitJoinAlgebraNode(JoinAlgebraNode node)
        {
            node.Left = VisitAlgebraNode(node.Left);
            node.Right = VisitAlgebraNode(node.Right);

            if (node.Predicate != null &&
                (node.OuterReferences == null || node.OuterReferences.Length == 0) &&
                (
                    node.Op == JoinAlgebraNode.JoinOperator.InnerJoin ||
                    node.Op == JoinAlgebraNode.JoinOperator.LeftOuterJoin ||
                    node.Op == JoinAlgebraNode.JoinOperator.RightOuterJoin ||
                    node.Op == JoinAlgebraNode.JoinOperator.FullOuterJoin)
                )
            {
                RowBufferEntry[] leftDefinedEntries = AstUtil.GetDefinedValueEntries(node.Left);
                RowBufferEntry[] rightDefinedEntries = AstUtil.GetDefinedValueEntries(node.Right);

                EqualPredicatesExtractor equalPredicatesExtractor = new EqualPredicatesExtractor(leftDefinedEntries, rightDefinedEntries);
                ExpressionNode probeResidual = equalPredicatesExtractor.VisitExpression(node.Predicate);
                BinaryExpression[] equalPredicates = equalPredicatesExtractor.GetEqualPredicates();

                if (equalPredicates.Length > 0)
                {
                    BinaryExpression equalPredicate = equalPredicates[0];

                    ExpressionBuilder expressionBuilder = new ExpressionBuilder();
                    expressionBuilder.Push(probeResidual);

                    if (equalPredicates.Length > 1)
                    {
                        for (int i = 1; i < equalPredicates.Length; i++)
                            expressionBuilder.Push(equalPredicates[i]);
                        expressionBuilder.PushNAry(LogicalOperator.And);
                    }

                    probeResidual = expressionBuilder.Pop();
                    if (probeResidual is ConstantExpression)
                        probeResidual = null;

                    AlgebraNode leftInput = node.Left;
                    AlgebraNode rightInput = node.Right;

                    if (node.Op == JoinAlgebraNode.JoinOperator.LeftOuterJoin)
                    {
                        node.Op = JoinAlgebraNode.JoinOperator.RightOuterJoin;
                        leftInput = node.Right;
                        rightInput = node.Left;
                        ExpressionNode oldLeft = equalPredicate.Left;
                        equalPredicate.Left = equalPredicate.Right;
                        equalPredicate.Right = oldLeft;
                    }

                    RowBufferEntry leftEntry;
                    RowBufferEntryExpression leftAsRowBufferEntryExpression = equalPredicate.Left as RowBufferEntryExpression;
                    if (leftAsRowBufferEntryExpression != null)
                    {
                        leftEntry = leftAsRowBufferEntryExpression.RowBufferEntry;
                    }
                    else
                    {
                        leftEntry = new RowBufferEntry(equalPredicate.Left.ExpressionType);
                        ComputedValueDefinition definedValue = new ComputedValueDefinition();
                        definedValue.Target = leftEntry;
                        definedValue.Expression = equalPredicate.Left;

                        ComputeScalarAlgebraNode computeScalarAlgebraNode = new ComputeScalarAlgebraNode();
                        computeScalarAlgebraNode.Input = leftInput;
                        computeScalarAlgebraNode.DefinedValues = new ComputedValueDefinition[] {definedValue};
                        leftInput = computeScalarAlgebraNode;
                    }

                    RowBufferEntry rightEntry;
                    RowBufferEntryExpression rightAsRowBufferEntryExpression = equalPredicate.Right as RowBufferEntryExpression;
                    if (rightAsRowBufferEntryExpression != null)
                    {
                        rightEntry = rightAsRowBufferEntryExpression.RowBufferEntry;
                    }
                    else
                    {
                        rightEntry = new RowBufferEntry(equalPredicate.Right.ExpressionType);
                        ComputedValueDefinition definedValue = new ComputedValueDefinition();
                        definedValue.Target = rightEntry;
                        definedValue.Expression = equalPredicate.Right;

                        ComputeScalarAlgebraNode computeScalarAlgebraNode = new ComputeScalarAlgebraNode();
                        computeScalarAlgebraNode.Input = rightInput;
                        computeScalarAlgebraNode.DefinedValues = new ComputedValueDefinition[] {definedValue};
                        rightInput = computeScalarAlgebraNode;
                    }

                    HashMatchAlgebraNode hashMatchAlgebraNode = new HashMatchAlgebraNode();
                    hashMatchAlgebraNode.Op = node.Op;
                    hashMatchAlgebraNode.Left = leftInput;
                    hashMatchAlgebraNode.Right = rightInput;
                    hashMatchAlgebraNode.BuildKeyEntry = leftEntry;
                    hashMatchAlgebraNode.ProbeEntry = rightEntry;
                    hashMatchAlgebraNode.ProbeResidual = probeResidual;
                    return hashMatchAlgebraNode;
                }
            }

            return node;
        }
Esempio n. 8
0
        public override AlgebraNode VisitJoinAlgebraNode(JoinAlgebraNode node)
        {
            node.Left  = VisitAlgebraNode(node.Left);
            node.Right = VisitAlgebraNode(node.Right);

            if (node.Predicate != null &&
                (node.OuterReferences == null || node.OuterReferences.Length == 0) &&
                (
                    node.Op == JoinAlgebraNode.JoinOperator.InnerJoin ||
                    node.Op == JoinAlgebraNode.JoinOperator.LeftOuterJoin ||
                    node.Op == JoinAlgebraNode.JoinOperator.RightOuterJoin ||
                    node.Op == JoinAlgebraNode.JoinOperator.FullOuterJoin)
                )
            {
                RowBufferEntry[] leftDefinedEntries  = AstUtil.GetDefinedValueEntries(node.Left);
                RowBufferEntry[] rightDefinedEntries = AstUtil.GetDefinedValueEntries(node.Right);

                EqualPredicatesExtractor equalPredicatesExtractor = new EqualPredicatesExtractor(leftDefinedEntries, rightDefinedEntries);
                ExpressionNode           probeResidual            = equalPredicatesExtractor.VisitExpression(node.Predicate);
                BinaryExpression[]       equalPredicates          = equalPredicatesExtractor.GetEqualPredicates();

                if (equalPredicates.Length > 0)
                {
                    BinaryExpression equalPredicate = equalPredicates[0];

                    ExpressionBuilder expressionBuilder = new ExpressionBuilder();
                    expressionBuilder.Push(probeResidual);

                    if (equalPredicates.Length > 1)
                    {
                        for (int i = 1; i < equalPredicates.Length; i++)
                        {
                            expressionBuilder.Push(equalPredicates[i]);
                        }
                        expressionBuilder.PushNAry(LogicalOperator.And);
                    }

                    probeResidual = expressionBuilder.Pop();
                    if (probeResidual is ConstantExpression)
                    {
                        probeResidual = null;
                    }

                    AlgebraNode leftInput  = node.Left;
                    AlgebraNode rightInput = node.Right;

                    if (node.Op == JoinAlgebraNode.JoinOperator.LeftOuterJoin)
                    {
                        node.Op    = JoinAlgebraNode.JoinOperator.RightOuterJoin;
                        leftInput  = node.Right;
                        rightInput = node.Left;
                        ExpressionNode oldLeft = equalPredicate.Left;
                        equalPredicate.Left  = equalPredicate.Right;
                        equalPredicate.Right = oldLeft;
                    }

                    RowBufferEntry           leftEntry;
                    RowBufferEntryExpression leftAsRowBufferEntryExpression = equalPredicate.Left as RowBufferEntryExpression;
                    if (leftAsRowBufferEntryExpression != null)
                    {
                        leftEntry = leftAsRowBufferEntryExpression.RowBufferEntry;
                    }
                    else
                    {
                        leftEntry = new RowBufferEntry(equalPredicate.Left.ExpressionType);
                        ComputedValueDefinition definedValue = new ComputedValueDefinition();
                        definedValue.Target     = leftEntry;
                        definedValue.Expression = equalPredicate.Left;

                        ComputeScalarAlgebraNode computeScalarAlgebraNode = new ComputeScalarAlgebraNode();
                        computeScalarAlgebraNode.Input         = leftInput;
                        computeScalarAlgebraNode.DefinedValues = new ComputedValueDefinition[] { definedValue };
                        leftInput = computeScalarAlgebraNode;
                    }

                    RowBufferEntry           rightEntry;
                    RowBufferEntryExpression rightAsRowBufferEntryExpression = equalPredicate.Right as RowBufferEntryExpression;
                    if (rightAsRowBufferEntryExpression != null)
                    {
                        rightEntry = rightAsRowBufferEntryExpression.RowBufferEntry;
                    }
                    else
                    {
                        rightEntry = new RowBufferEntry(equalPredicate.Right.ExpressionType);
                        ComputedValueDefinition definedValue = new ComputedValueDefinition();
                        definedValue.Target     = rightEntry;
                        definedValue.Expression = equalPredicate.Right;

                        ComputeScalarAlgebraNode computeScalarAlgebraNode = new ComputeScalarAlgebraNode();
                        computeScalarAlgebraNode.Input         = rightInput;
                        computeScalarAlgebraNode.DefinedValues = new ComputedValueDefinition[] { definedValue };
                        rightInput = computeScalarAlgebraNode;
                    }

                    HashMatchAlgebraNode hashMatchAlgebraNode = new HashMatchAlgebraNode();
                    hashMatchAlgebraNode.Op            = node.Op;
                    hashMatchAlgebraNode.Left          = leftInput;
                    hashMatchAlgebraNode.Right         = rightInput;
                    hashMatchAlgebraNode.BuildKeyEntry = leftEntry;
                    hashMatchAlgebraNode.ProbeEntry    = rightEntry;
                    hashMatchAlgebraNode.ProbeResidual = probeResidual;
                    return(hashMatchAlgebraNode);
                }
            }

            return(node);
        }
Esempio n. 9
0
		public override QueryNode VisitBinaryQuery(BinaryQuery query)
		{
			switch (query.Op)
			{
				case BinaryQueryOperator.Intersect:
				case BinaryQueryOperator.Except:
				{
					ResultAlgebraNode left = ((ResultAlgebraNode)ConvertAstNode(query.Left));
					ResultAlgebraNode right = ((ResultAlgebraNode)ConvertAstNode(query.Right));

					// Create distinct sort

					SortAlgebraNode sortAlgebraNode = new SortAlgebraNode();
					sortAlgebraNode.Distinct = true;
					sortAlgebraNode.Input = left;
					sortAlgebraNode.SortEntries = left.OutputList;
					sortAlgebraNode.SortOrders = CreateAscendingSortOrders(sortAlgebraNode.SortEntries.Length);

					// Insert left (anti) semi join to (except) intersect left and right.

					ExpressionBuilder expressionBuilder = new ExpressionBuilder();
					for (int i = 0; i < left.OutputList.Length; i++)
					{
						RowBufferEntryExpression leftExpr = new RowBufferEntryExpression();
						leftExpr.RowBufferEntry = left.OutputList[i];

						RowBufferEntryExpression rightExpr = new RowBufferEntryExpression();
						rightExpr.RowBufferEntry = right.OutputList[i];

						expressionBuilder.Push(leftExpr);
						expressionBuilder.Push(rightExpr);
						expressionBuilder.PushBinary(BinaryOperator.Equal);
						expressionBuilder.Push(leftExpr);
						expressionBuilder.PushIsNull();
						expressionBuilder.Push(rightExpr);
						expressionBuilder.PushIsNull();
						expressionBuilder.PushBinary(BinaryOperator.LogicalAnd);
						expressionBuilder.PushBinary(BinaryOperator.LogicalOr);
					}
					expressionBuilder.PushNAry(LogicalOperator.And);
					ExpressionNode joinCondition = expressionBuilder.Pop();

					JoinAlgebraNode joinAlgebraNode = new JoinAlgebraNode();
					if (query.Op == BinaryQueryOperator.Intersect)
						joinAlgebraNode.Op = JoinAlgebraNode.JoinOperator.LeftSemiJoin;
					else
						joinAlgebraNode.Op = JoinAlgebraNode.JoinOperator.LeftAntiSemiJoin;
					joinAlgebraNode.Left = sortAlgebraNode;
					joinAlgebraNode.Right = right;
					joinAlgebraNode.Predicate = joinCondition;
					SetLastAlgebraNode(joinAlgebraNode);

					ResultAlgebraNode resultAlgebraNode = new ResultAlgebraNode();
					resultAlgebraNode.Input = GetLastAlgebraNode();
					resultAlgebraNode.OutputList = left.OutputList;
					resultAlgebraNode.ColumnNames = left.ColumnNames;
					SetLastAlgebraNode(resultAlgebraNode);
					break;
				}

				case BinaryQueryOperator.Union:
				case BinaryQueryOperator.UnionAll:
				{
					// Build a flat list with all inputs.

					List<QueryNode> inputList = AstUtil.FlattenBinaryQuery(query);

					AlgebraNode[] inputs = new AlgebraNode[inputList.Count];
					for (int i = 0; i < inputs.Length; i++)
						inputs[i] = ConvertAstNode(inputList[i]);

					int outputColumnCount = inputs[0].OutputList.Length;

					UnitedValueDefinition[] definedValues = new UnitedValueDefinition[outputColumnCount];
					List<RowBufferEntry> definedValueEntries = new List<RowBufferEntry>();

					for (int i = 0; i < outputColumnCount; i++)
					{
						RowBufferEntry rowBufferEntry = new RowBufferEntry(inputs[0].OutputList[i].DataType);
						definedValueEntries.Add(rowBufferEntry);

						UnitedValueDefinition definedValue = new UnitedValueDefinition();
						definedValue.Target = rowBufferEntry;

						List<RowBufferEntry> dependencies = new List<RowBufferEntry>();
						foreach (ResultAlgebraNode node in inputs)
							dependencies.Add(node.OutputList[i]);
						definedValue.DependendEntries = dependencies.ToArray();

						definedValues[i] = definedValue;
					}

					ConcatAlgebraNode concatAlgebraNode = new ConcatAlgebraNode();
					concatAlgebraNode.Inputs = inputs;
					concatAlgebraNode.DefinedValues = definedValues;
					SetLastAlgebraNode(concatAlgebraNode);

					if (query.Op == BinaryQueryOperator.Union)
					{
						SortAlgebraNode sortAlgebraNode = new SortAlgebraNode();
						sortAlgebraNode.Distinct = true;
						sortAlgebraNode.Input = GetLastAlgebraNode();
						sortAlgebraNode.SortEntries = definedValueEntries.ToArray();
						sortAlgebraNode.SortOrders = CreateAscendingSortOrders(sortAlgebraNode.SortEntries.Length);
						SetLastAlgebraNode(sortAlgebraNode);
					}

					ResultAlgebraNode unionResultAlgebraNode = new ResultAlgebraNode();
					unionResultAlgebraNode.Input = GetLastAlgebraNode();
					unionResultAlgebraNode.ColumnNames = ((ResultAlgebraNode)inputs[0]).ColumnNames;
					unionResultAlgebraNode.OutputList = definedValueEntries.ToArray();
					SetLastAlgebraNode(unionResultAlgebraNode);

					break;
				}
			}

			return query;
		}