private void PushOuterReferences(object[] rowBuffer, JoinAlgebraNode node)
{
if (node.OuterReferences != null && node.OuterReferences.Length > 0)
{
// Important: We cannot use node.OuterReferences as argument for BoundRowBufferEntrySet().
// The replacment strategy below will replace occurences to the entries by their index
// within the array. Therefore we need an array with the same layout as the row buffer.
RowBufferEntry[] outerReferences = new RowBufferEntry[node.Left.OutputList.Length];
for (int i = 0; i < outerReferences.Length; i++)
{
if (ArrayHelpers.Contains(node.OuterReferences, node.Left.OutputList[i]))
{
outerReferences[i] = node.Left.OutputList[i];
}
}
BoundRowBufferEntrySet bufferEntrySet = new BoundRowBufferEntrySet(rowBuffer, outerReferences);
_outerReferenceStack.Push(bufferEntrySet);
}
}
public override AlgebraNode VisitJoinAlgebraNode(JoinAlgebraNode node)
{
if (node.Op == JoinAlgebraNode.JoinOperator.RightOuterJoin ||
node.Op == JoinAlgebraNode.JoinOperator.RightAntiSemiJoin ||
node.Op == JoinAlgebraNode.JoinOperator.RightSemiJoin)
{
if (node.OuterReferences != null && node.OuterReferences.Length > 0)
{
throw ExceptionBuilder.InternalError("Outer references should not be possible for {0} and are not supported.", node.Op);
}
node.SwapSides();
}
NestedLoopsIterator nestedLoopsIterator;
switch (node.Op)
{
case JoinAlgebraNode.JoinOperator.InnerJoin:
nestedLoopsIterator = new InnerNestedLoopsIterator();
break;
case JoinAlgebraNode.JoinOperator.LeftOuterJoin:
nestedLoopsIterator = new LeftOuterNestedLoopsIterator();
break;
case JoinAlgebraNode.JoinOperator.LeftSemiJoin:
if (node.ProbeBufferEntry == null)
{
nestedLoopsIterator = new LeftSemiNestedLoopsIterator();
}
else
{
ProbedSemiJoinNestedLoopsIterator probedSemiJoinNestedLoopsIterator = new ProbedSemiJoinNestedLoopsIterator();
probedSemiJoinNestedLoopsIterator.ProbeOutput = GetDefinedValue(node.OutputList, node.ProbeBufferEntry);
nestedLoopsIterator = probedSemiJoinNestedLoopsIterator;
}
break;
case JoinAlgebraNode.JoinOperator.LeftAntiSemiJoin:
if (node.ProbeBufferEntry == null)
{
nestedLoopsIterator = new LeftAntiSemiNestedLoopsIterator();
}
else
{
ProbedAntiSemiJoinNestedLoopsIterator probedSemiJoinNestedLoopsIterator = new ProbedAntiSemiJoinNestedLoopsIterator();
probedSemiJoinNestedLoopsIterator.ProbeOutput = GetDefinedValue(node.OutputList, node.ProbeBufferEntry);
nestedLoopsIterator = probedSemiJoinNestedLoopsIterator;
}
break;
default:
throw ExceptionBuilder.UnhandledCaseLabel(node.Op);
}
nestedLoopsIterator.RowBuffer = new object[node.OutputList.Length];
nestedLoopsIterator.Left = ConvertAlgebraNode(node.Left);
nestedLoopsIterator.LeftOutput = GetIteratorOutput(0, node.Left.OutputList, node.OutputList);
PushOuterReferences(nestedLoopsIterator.Left.RowBuffer, node);
nestedLoopsIterator.Right = ConvertAlgebraNode(node.Right);
nestedLoopsIterator.RightOutput = GetIteratorOutput(nestedLoopsIterator.LeftOutput.Length, node.Right.OutputList, node.OutputList);
UpdatePredicateRowBufferReferences(nestedLoopsIterator, node);
if (node.OuterReferences != null && node.OuterReferences.Length > 0)
{
_outerReferenceStack.Pop();
}
SetLastIterator(node, nestedLoopsIterator);
return(node);
}
private void UpdatePredicateRowBufferReferences(NestedLoopsIterator nestedLoopsIterator, JoinAlgebraNode node)
{
BoundRowBufferEntrySet leftBoundRowBufferEntrySet = new BoundRowBufferEntrySet(nestedLoopsIterator.Left.RowBuffer, node.Left.OutputList);
BoundRowBufferEntrySet rightBoundRowBufferEntrySet = new BoundRowBufferEntrySet(nestedLoopsIterator.Right.RowBuffer, node.Right.OutputList);
if (node.Predicate != null)
{
nestedLoopsIterator.Predicate = CreateRuntimeExpression(node.Predicate, leftBoundRowBufferEntrySet, rightBoundRowBufferEntrySet);
}
if (node.PassthruPredicate != null)
{
nestedLoopsIterator.PassthruPredicate = CreateRuntimeExpression(node.PassthruPredicate, leftBoundRowBufferEntrySet, rightBoundRowBufferEntrySet);
}
}
