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 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);
}
private static ResultAlgebraNode CreateAssertedSubquery(ResultAlgebraNode inputNode)
{
if (AstUtil.WillProduceAtMostOneRow(inputNode))
return inputNode;
RowBufferEntry inputEntry = inputNode.OutputList[0];
AggregatedValueDefinition countDefinedValue = new AggregatedValueDefinition();
countDefinedValue.Aggregate = new CountAggregateBinding("COUNT");
countDefinedValue.Aggregator = countDefinedValue.Aggregate.CreateAggregator(typeof(int));
countDefinedValue.Argument = LiteralExpression.FromInt32(0);
RowBufferEntry countDefinedValueEntry = new RowBufferEntry(countDefinedValue.Aggregator.ReturnType);
countDefinedValue.Target = countDefinedValueEntry;
RowBufferEntryExpression anyAggregateArgument = new RowBufferEntryExpression();
anyAggregateArgument.RowBufferEntry = inputEntry;
AggregatedValueDefinition anyDefinedValue = new AggregatedValueDefinition();
anyDefinedValue.Aggregate = new FirstAggregateBinding("ANY");
anyDefinedValue.Aggregator = anyDefinedValue.Aggregate.CreateAggregator(inputEntry.DataType);
anyDefinedValue.Argument = anyAggregateArgument;
RowBufferEntry anyDefinedValueEntry = new RowBufferEntry(inputEntry.DataType);
anyDefinedValue.Target = anyDefinedValueEntry;
AggregateAlgebraNode aggregateAlgebraNode = new AggregateAlgebraNode();
aggregateAlgebraNode.Input = inputNode.Input;
aggregateAlgebraNode.DefinedValues = new AggregatedValueDefinition[] { countDefinedValue, anyDefinedValue };
// CASE WHEN SubqueryCount > 1 THEN 0 ELSE NULL END
ExpressionBuilder expressionBuilder = new ExpressionBuilder();
expressionBuilder.Push(new RowBufferEntryExpression(countDefinedValueEntry));
expressionBuilder.Push(LiteralExpression.FromInt32(1));
expressionBuilder.PushBinary(BinaryOperator.Greater);
ExpressionNode whenExpression = expressionBuilder.Pop();
ExpressionNode thenExpression = LiteralExpression.FromInt32(0);
CaseExpression caseExpression = new CaseExpression();
caseExpression.WhenExpressions = new ExpressionNode[] { whenExpression };
caseExpression.ThenExpressions = new ExpressionNode[] { thenExpression };
expressionBuilder.Push(caseExpression);
ExpressionNode predicate = expressionBuilder.Pop();
AssertAlgebraNode assertAlgebraNode = new AssertAlgebraNode();
assertAlgebraNode.Input = aggregateAlgebraNode;
assertAlgebraNode.Predicate = predicate;
assertAlgebraNode.AssertionType = AssertionType.MaxOneRow;
ResultAlgebraNode resultAlgebraNode = new ResultAlgebraNode();
resultAlgebraNode.Input = assertAlgebraNode;
resultAlgebraNode.OutputList = new RowBufferEntry[] { anyDefinedValueEntry };
resultAlgebraNode.ColumnNames = inputNode.ColumnNames;
return resultAlgebraNode;
}
private static AlgebraNode AlgebrizeRecursiveCte(CommonTableBinding commonTableBinding)
{
// It is a recursive query.
//
// Create row buffer entry that is used to guard the recursion and the primary table spool
// that spools the results needed by nested recursion calls.
ExpressionBuilder expressionBuilder = new ExpressionBuilder();
StackedTableSpoolAlgebraNode primaryTableSpool = new StackedTableSpoolAlgebraNode();
RowBufferEntry anchorRecursionLevel;
RowBufferEntry[] anchorOutput;
AlgebraNode anchorNode;
#region Anchor member
{
// Emit anchor member.
AlgebraNode algebrizedAnchor = Convert(commonTableBinding.AnchorMember);
// Emit compute scalar that initializes the recursion level to 0.
anchorRecursionLevel = new RowBufferEntry(typeof(int));
ComputedValueDefinition computedValueDefinition1 = new ComputedValueDefinition();
computedValueDefinition1.Target = anchorRecursionLevel;
computedValueDefinition1.Expression = LiteralExpression.FromInt32(0);
ComputeScalarAlgebraNode computeScalarAlgebraNode = new ComputeScalarAlgebraNode();
computeScalarAlgebraNode.Input = algebrizedAnchor;
computeScalarAlgebraNode.DefinedValues = new ComputedValueDefinition[] { computedValueDefinition1 };
anchorOutput = algebrizedAnchor.OutputList;
anchorNode = computeScalarAlgebraNode;
}
#endregion
RowBufferEntry incrementedRecursionLevel;
RowBufferEntry[] tableSpoolOutput;
AlgebraNode tableSpoolNode;
#region Table spool
{
// Emit table spool reference.
RowBufferEntry recursionLevelRefEntry = new RowBufferEntry(typeof(int));
tableSpoolOutput = new RowBufferEntry[anchorOutput.Length];
for (int i = 0; i < tableSpoolOutput.Length; i++)
{
tableSpoolOutput[i] = new RowBufferEntry(anchorOutput[i].DataType);
}
StackedTableSpoolRefAlgebraNode tableSpoolReference = new StackedTableSpoolRefAlgebraNode();
tableSpoolReference.PrimarySpool = primaryTableSpool;
tableSpoolReference.DefinedValues = ArrayHelpers.JoinArrays(new RowBufferEntry[] { recursionLevelRefEntry }, tableSpoolOutput);
// Emit compute scalar that increases the recursion level by one and renames
// columns from the spool to the CTE column buffer entries.
expressionBuilder.Push(new RowBufferEntryExpression(recursionLevelRefEntry));
expressionBuilder.Push(LiteralExpression.FromInt32(1));
expressionBuilder.PushBinary(BinaryOperator.Add);
incrementedRecursionLevel = new RowBufferEntry(typeof(int));
ComputedValueDefinition incremenedRecLevelValueDefinition = new ComputedValueDefinition();
incremenedRecLevelValueDefinition.Target = incrementedRecursionLevel;
incremenedRecLevelValueDefinition.Expression = expressionBuilder.Pop();
CteColumnMappingFinder cteColumnMappingFinder = new CteColumnMappingFinder(commonTableBinding, tableSpoolOutput);
foreach (QueryNode recursiveMember in commonTableBinding.RecursiveMembers)
{
cteColumnMappingFinder.Visit(recursiveMember);
}
CteColumnMapping[] cteColumnMappings = cteColumnMappingFinder.GetMappings();
List <ComputedValueDefinition> definedValues = new List <ComputedValueDefinition>();
definedValues.Add(incremenedRecLevelValueDefinition);
foreach (CteColumnMapping cteColumnMapping in cteColumnMappings)
{
ComputedValueDefinition definedValue = new ComputedValueDefinition();
definedValue.Target = cteColumnMapping.VirtualBufferEntry;
definedValue.Expression = new RowBufferEntryExpression(cteColumnMapping.SpoolBufferEntry);
definedValues.Add(definedValue);
}
ComputeScalarAlgebraNode computeScalarAlgebraNode = new ComputeScalarAlgebraNode();
computeScalarAlgebraNode.Input = tableSpoolReference;
computeScalarAlgebraNode.DefinedValues = definedValues.ToArray();
tableSpoolNode = computeScalarAlgebraNode;
}
#endregion
RowBufferEntry[] recursiveOutput;
AlgebraNode recursiveNode;
#region Recursive member(s)
{
// Emit all recursive parts. The join conditions to the recursive part are replaced by simple filters
// in the nested Convert() call.
ConcatAlgebraNode concatAlgebraNode = new ConcatAlgebraNode();
concatAlgebraNode.Inputs = new AlgebraNode[commonTableBinding.RecursiveMembers.Length];
for (int i = 0; i < commonTableBinding.RecursiveMembers.Length; i++)
{
concatAlgebraNode.Inputs[i] = Convert(commonTableBinding, commonTableBinding.RecursiveMembers[i]);
}
concatAlgebraNode.DefinedValues = new UnitedValueDefinition[anchorOutput.Length];
for (int i = 0; i < anchorOutput.Length; i++)
{
List <RowBufferEntry> dependencies = new List <RowBufferEntry>();
foreach (ResultAlgebraNode algebrizedRecursivePart in concatAlgebraNode.Inputs)
{
dependencies.Add(algebrizedRecursivePart.OutputList[i]);
}
concatAlgebraNode.DefinedValues[i] = new UnitedValueDefinition();
concatAlgebraNode.DefinedValues[i].Target = new RowBufferEntry(anchorOutput[i].DataType);
concatAlgebraNode.DefinedValues[i].DependendEntries = dependencies.ToArray();
}
// Calculate the recursive output.
recursiveOutput = new RowBufferEntry[concatAlgebraNode.DefinedValues.Length];
for (int i = 0; i < concatAlgebraNode.DefinedValues.Length; i++)
{
recursiveOutput[i] = concatAlgebraNode.DefinedValues[i].Target;
}
// Emit cross join
JoinAlgebraNode crossJoinNode = new JoinAlgebraNode();
crossJoinNode.Left = tableSpoolNode;
crossJoinNode.Right = concatAlgebraNode;
// Emit assert that ensures that the recursion level is <= 100.
expressionBuilder.Push(new RowBufferEntryExpression(incrementedRecursionLevel));
expressionBuilder.Push(LiteralExpression.FromInt32(100));
expressionBuilder.PushBinary(BinaryOperator.Greater);
CaseExpression caseExpression = new CaseExpression();
caseExpression.WhenExpressions = new ExpressionNode[1];
caseExpression.WhenExpressions[0] = expressionBuilder.Pop();
caseExpression.ThenExpressions = new ExpressionNode[1];
caseExpression.ThenExpressions[0] = LiteralExpression.FromInt32(0);
AssertAlgebraNode assertAlgebraNode = new AssertAlgebraNode();
assertAlgebraNode.Input = crossJoinNode;
assertAlgebraNode.AssertionType = AssertionType.BelowRecursionLimit;
assertAlgebraNode.Predicate = caseExpression;
recursiveNode = assertAlgebraNode;
}
#endregion
RowBufferEntry[] algebrizedOutput;
AlgebraNode algebrizedCte;
#region Combination
{
// Create concat node to combine anchor and recursive part.
ConcatAlgebraNode concatAlgebraNode = new ConcatAlgebraNode();
concatAlgebraNode.Inputs = new AlgebraNode[2];
concatAlgebraNode.Inputs[0] = anchorNode;
concatAlgebraNode.Inputs[1] = recursiveNode;
concatAlgebraNode.DefinedValues = new UnitedValueDefinition[anchorOutput.Length + 1];
concatAlgebraNode.DefinedValues[0] = new UnitedValueDefinition();
concatAlgebraNode.DefinedValues[0].Target = new RowBufferEntry(anchorRecursionLevel.DataType);
concatAlgebraNode.DefinedValues[0].DependendEntries = new RowBufferEntry[] { anchorRecursionLevel, incrementedRecursionLevel };
for (int i = 0; i < anchorOutput.Length; i++)
{
concatAlgebraNode.DefinedValues[i + 1] = new UnitedValueDefinition();
concatAlgebraNode.DefinedValues[i + 1].Target = new RowBufferEntry(anchorOutput[i].DataType);
concatAlgebraNode.DefinedValues[i + 1].DependendEntries = new RowBufferEntry[] { anchorOutput[i], recursiveOutput[i] };
}
algebrizedOutput = new RowBufferEntry[concatAlgebraNode.DefinedValues.Length];
for (int i = 0; i < concatAlgebraNode.DefinedValues.Length; i++)
{
algebrizedOutput[i] = concatAlgebraNode.DefinedValues[i].Target;
}
// Assign the combination as the input to the primray spool
primaryTableSpool.Input = concatAlgebraNode;
// The primary spool represents the result of the "inlined" CTE.
algebrizedCte = primaryTableSpool;
}
#endregion
algebrizedCte.OutputList = algebrizedOutput;
return(algebrizedCte);
}
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));
}
}
private static ResultAlgebraNode CreateAssertedSubquery(ResultAlgebraNode inputNode)
{
if (AstUtil.WillProduceAtMostOneRow(inputNode))
{
return(inputNode);
}
RowBufferEntry inputEntry = inputNode.OutputList[0];
AggregatedValueDefinition countDefinedValue = new AggregatedValueDefinition();
countDefinedValue.Aggregate = new CountAggregateBinding("COUNT");
countDefinedValue.Aggregator = countDefinedValue.Aggregate.CreateAggregator(typeof(int));
countDefinedValue.Argument = LiteralExpression.FromInt32(0);
RowBufferEntry countDefinedValueEntry = new RowBufferEntry(countDefinedValue.Aggregator.ReturnType);
countDefinedValue.Target = countDefinedValueEntry;
RowBufferEntryExpression anyAggregateArgument = new RowBufferEntryExpression();
anyAggregateArgument.RowBufferEntry = inputEntry;
AggregatedValueDefinition anyDefinedValue = new AggregatedValueDefinition();
anyDefinedValue.Aggregate = new FirstAggregateBinding("ANY");
anyDefinedValue.Aggregator = anyDefinedValue.Aggregate.CreateAggregator(inputEntry.DataType);
anyDefinedValue.Argument = anyAggregateArgument;
RowBufferEntry anyDefinedValueEntry = new RowBufferEntry(inputEntry.DataType);
anyDefinedValue.Target = anyDefinedValueEntry;
AggregateAlgebraNode aggregateAlgebraNode = new AggregateAlgebraNode();
aggregateAlgebraNode.Input = inputNode.Input;
aggregateAlgebraNode.DefinedValues = new AggregatedValueDefinition[] { countDefinedValue, anyDefinedValue };
// CASE WHEN SubqueryCount > 1 THEN 0 ELSE NULL END
ExpressionBuilder expressionBuilder = new ExpressionBuilder();
expressionBuilder.Push(new RowBufferEntryExpression(countDefinedValueEntry));
expressionBuilder.Push(LiteralExpression.FromInt32(1));
expressionBuilder.PushBinary(BinaryOperator.Greater);
ExpressionNode whenExpression = expressionBuilder.Pop();
ExpressionNode thenExpression = LiteralExpression.FromInt32(0);
CaseExpression caseExpression = new CaseExpression();
caseExpression.WhenExpressions = new ExpressionNode[] { whenExpression };
caseExpression.ThenExpressions = new ExpressionNode[] { thenExpression };
expressionBuilder.Push(caseExpression);
ExpressionNode predicate = expressionBuilder.Pop();
AssertAlgebraNode assertAlgebraNode = new AssertAlgebraNode();
assertAlgebraNode.Input = aggregateAlgebraNode;
assertAlgebraNode.Predicate = predicate;
assertAlgebraNode.AssertionType = AssertionType.MaxOneRow;
ResultAlgebraNode resultAlgebraNode = new ResultAlgebraNode();
resultAlgebraNode.Input = assertAlgebraNode;
resultAlgebraNode.OutputList = new RowBufferEntry[] { anyDefinedValueEntry };
resultAlgebraNode.ColumnNames = inputNode.ColumnNames;
return(resultAlgebraNode);
}
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;
}
private static AlgebraNode AlgebrizeRecursiveCte(CommonTableBinding commonTableBinding)
{
// It is a recursive query.
//
// Create row buffer entry that is used to guard the recursion and the primary table spool
// that spools the results needed by nested recursion calls.
ExpressionBuilder expressionBuilder = new ExpressionBuilder();
StackedTableSpoolAlgebraNode primaryTableSpool = new StackedTableSpoolAlgebraNode();
RowBufferEntry anchorRecursionLevel;
RowBufferEntry[] anchorOutput;
AlgebraNode anchorNode;
#region Anchor member
{
// Emit anchor member.
AlgebraNode algebrizedAnchor = Convert(commonTableBinding.AnchorMember);
// Emit compute scalar that initializes the recursion level to 0.
anchorRecursionLevel = new RowBufferEntry(typeof(int));
ComputedValueDefinition computedValueDefinition1 = new ComputedValueDefinition();
computedValueDefinition1.Target = anchorRecursionLevel;
computedValueDefinition1.Expression = LiteralExpression.FromInt32(0);
ComputeScalarAlgebraNode computeScalarAlgebraNode = new ComputeScalarAlgebraNode();
computeScalarAlgebraNode.Input = algebrizedAnchor;
computeScalarAlgebraNode.DefinedValues = new ComputedValueDefinition[] { computedValueDefinition1 };
anchorOutput = algebrizedAnchor.OutputList;
anchorNode = computeScalarAlgebraNode;
}
#endregion
RowBufferEntry incrementedRecursionLevel;
RowBufferEntry[] tableSpoolOutput;
AlgebraNode tableSpoolNode;
#region Table spool
{
// Emit table spool reference.
RowBufferEntry recursionLevelRefEntry = new RowBufferEntry(typeof(int));
tableSpoolOutput = new RowBufferEntry[anchorOutput.Length];
for (int i = 0; i < tableSpoolOutput.Length; i++)
tableSpoolOutput[i] = new RowBufferEntry(anchorOutput[i].DataType);
StackedTableSpoolRefAlgebraNode tableSpoolReference = new StackedTableSpoolRefAlgebraNode();
tableSpoolReference.PrimarySpool = primaryTableSpool;
tableSpoolReference.DefinedValues = ArrayHelpers.JoinArrays(new RowBufferEntry[] { recursionLevelRefEntry }, tableSpoolOutput);
// Emit compute scalar that increases the recursion level by one and renames
// columns from the spool to the CTE column buffer entries.
expressionBuilder.Push(new RowBufferEntryExpression(recursionLevelRefEntry));
expressionBuilder.Push(LiteralExpression.FromInt32(1));
expressionBuilder.PushBinary(BinaryOperator.Add);
incrementedRecursionLevel = new RowBufferEntry(typeof(int));
ComputedValueDefinition incremenedRecLevelValueDefinition = new ComputedValueDefinition();
incremenedRecLevelValueDefinition.Target = incrementedRecursionLevel;
incremenedRecLevelValueDefinition.Expression = expressionBuilder.Pop();
CteColumnMappingFinder cteColumnMappingFinder = new CteColumnMappingFinder(commonTableBinding, tableSpoolOutput);
foreach (QueryNode recursiveMember in commonTableBinding.RecursiveMembers)
cteColumnMappingFinder.Visit(recursiveMember);
CteColumnMapping[] cteColumnMappings = cteColumnMappingFinder.GetMappings();
List<ComputedValueDefinition> definedValues = new List<ComputedValueDefinition>();
definedValues.Add(incremenedRecLevelValueDefinition);
foreach (CteColumnMapping cteColumnMapping in cteColumnMappings)
{
ComputedValueDefinition definedValue = new ComputedValueDefinition();
definedValue.Target = cteColumnMapping.VirtualBufferEntry;
definedValue.Expression = new RowBufferEntryExpression(cteColumnMapping.SpoolBufferEntry);
definedValues.Add(definedValue);
}
ComputeScalarAlgebraNode computeScalarAlgebraNode = new ComputeScalarAlgebraNode();
computeScalarAlgebraNode.Input = tableSpoolReference;
computeScalarAlgebraNode.DefinedValues = definedValues.ToArray();
tableSpoolNode = computeScalarAlgebraNode;
}
#endregion
RowBufferEntry[] recursiveOutput;
AlgebraNode recursiveNode;
#region Recursive member(s)
{
// Emit all recursive parts. The join conditions to the recursive part are replaced by simple filters
// in the nested Convert() call.
ConcatAlgebraNode concatAlgebraNode = new ConcatAlgebraNode();
concatAlgebraNode.Inputs = new AlgebraNode[commonTableBinding.RecursiveMembers.Length];
for (int i = 0; i < commonTableBinding.RecursiveMembers.Length; i++)
concatAlgebraNode.Inputs[i] = Convert(commonTableBinding, commonTableBinding.RecursiveMembers[i]);
concatAlgebraNode.DefinedValues = new UnitedValueDefinition[anchorOutput.Length];
for (int i = 0; i < anchorOutput.Length; i++)
{
List<RowBufferEntry> dependencies = new List<RowBufferEntry>();
foreach (ResultAlgebraNode algebrizedRecursivePart in concatAlgebraNode.Inputs)
dependencies.Add(algebrizedRecursivePart.OutputList[i]);
concatAlgebraNode.DefinedValues[i] = new UnitedValueDefinition();
concatAlgebraNode.DefinedValues[i].Target = new RowBufferEntry(anchorOutput[i].DataType);
concatAlgebraNode.DefinedValues[i].DependendEntries = dependencies.ToArray();
}
// Calculate the recursive output.
recursiveOutput = new RowBufferEntry[concatAlgebraNode.DefinedValues.Length];
for (int i = 0; i < concatAlgebraNode.DefinedValues.Length; i++)
recursiveOutput[i] = concatAlgebraNode.DefinedValues[i].Target;
// Emit cross join
JoinAlgebraNode crossJoinNode = new JoinAlgebraNode();
crossJoinNode.Left = tableSpoolNode;
crossJoinNode.Right = concatAlgebraNode;
// Emit assert that ensures that the recursion level is <= 100.
expressionBuilder.Push(new RowBufferEntryExpression(incrementedRecursionLevel));
expressionBuilder.Push(LiteralExpression.FromInt32(100));
expressionBuilder.PushBinary(BinaryOperator.Greater);
CaseExpression caseExpression = new CaseExpression();
caseExpression.WhenExpressions = new ExpressionNode[1];
caseExpression.WhenExpressions[0] = expressionBuilder.Pop();
caseExpression.ThenExpressions = new ExpressionNode[1];
caseExpression.ThenExpressions[0] = LiteralExpression.FromInt32(0);
AssertAlgebraNode assertAlgebraNode = new AssertAlgebraNode();
assertAlgebraNode.Input = crossJoinNode;
assertAlgebraNode.AssertionType = AssertionType.BelowRecursionLimit;
assertAlgebraNode.Predicate = caseExpression;
recursiveNode = assertAlgebraNode;
}
#endregion
RowBufferEntry[] algebrizedOutput;
AlgebraNode algebrizedCte;
#region Combination
{
// Create concat node to combine anchor and recursive part.
ConcatAlgebraNode concatAlgebraNode = new ConcatAlgebraNode();
concatAlgebraNode.Inputs = new AlgebraNode[2];
concatAlgebraNode.Inputs[0] = anchorNode;
concatAlgebraNode.Inputs[1] = recursiveNode;
concatAlgebraNode.DefinedValues = new UnitedValueDefinition[anchorOutput.Length + 1];
concatAlgebraNode.DefinedValues[0] = new UnitedValueDefinition();
concatAlgebraNode.DefinedValues[0].Target = new RowBufferEntry(anchorRecursionLevel.DataType);
concatAlgebraNode.DefinedValues[0].DependendEntries = new RowBufferEntry[] { anchorRecursionLevel, incrementedRecursionLevel };
for (int i = 0; i < anchorOutput.Length; i++)
{
concatAlgebraNode.DefinedValues[i + 1] = new UnitedValueDefinition();
concatAlgebraNode.DefinedValues[i + 1].Target = new RowBufferEntry(anchorOutput[i].DataType);
concatAlgebraNode.DefinedValues[i + 1].DependendEntries = new RowBufferEntry[] { anchorOutput[i], recursiveOutput[i] };
}
algebrizedOutput = new RowBufferEntry[concatAlgebraNode.DefinedValues.Length];
for (int i = 0; i < concatAlgebraNode.DefinedValues.Length; i++)
algebrizedOutput[i] = concatAlgebraNode.DefinedValues[i].Target;
// Assign the combination as the input to the primray spool
primaryTableSpool.Input = concatAlgebraNode;
// The primary spool represents the result of the "inlined" CTE.
algebrizedCte = primaryTableSpool;
}
#endregion
algebrizedCte.OutputList = algebrizedOutput;
return algebrizedCte;
}
