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);
}
