//---------------------------------------------------------------------------------------
// Instantiates a new hash-join enumerator.
//
internal HashJoinQueryOperatorEnumerator(
QueryOperatorEnumerator <Pair <TLeftInput, THashKey>, TLeftKey> leftSource,
HashLookupBuilder <TRightInput, TRightKey, THashKey> rightLookupBuilder,
Func <TLeftInput, TRightInput, TOutput> resultSelector,
HashJoinOutputKeyBuilder <TLeftKey, TRightKey, TOutputKey> outputKeyBuilder,
CancellationToken cancellationToken)
{
Debug.Assert(leftSource != null);
Debug.Assert(rightLookupBuilder != null);
Debug.Assert(resultSelector != null);
Debug.Assert(outputKeyBuilder != null);
_leftSource = leftSource;
_rightLookupBuilder = rightLookupBuilder;
_resultSelector = resultSelector;
_outputKeyBuilder = outputKeyBuilder;
_cancellationToken = cancellationToken;
}
//---------------------------------------------------------------------------------------
// This is a helper method. WrapPartitionedStream decides what type TLeftKey is going
// to be, and then call this method with that key as a generic parameter.
//
private void WrapPartitionedStreamHelper <TLeftKey, TRightKey>(
PartitionedStream <Pair <TLeftInput, TKey>, TLeftKey> leftHashStream, PartitionedStream <TRightInput, TRightKey> rightPartitionedStream,
IPartitionedStreamRecipient <TOutput> outputRecipient, int partitionCount, CancellationToken cancellationToken)
{
if (RightChild.OutputOrdered)
{
PartitionedStream <Pair <TRightInput, TKey>, TRightKey> rePartitionedRightStream = ExchangeUtilities.HashRepartitionOrdered(
rightPartitionedStream, _rightKeySelector, _keyComparer, null, cancellationToken);
HashLookupBuilder <IEnumerable <TRightInput>, Pair <bool, TRightKey>, TKey>[] rightLookupBuilders =
new HashLookupBuilder <IEnumerable <TRightInput>, Pair <bool, TRightKey>, TKey> [partitionCount];
for (int i = 0; i < partitionCount; i++)
{
rightLookupBuilders[i] = new OrderedGroupJoinHashLookupBuilder <TRightInput, TRightKey, TKey>(
rePartitionedRightStream[i], _keyComparer, rePartitionedRightStream.KeyComparer);
}
WrapPartitionedStreamHelper <TLeftKey, Pair <bool, TRightKey> >(leftHashStream, rightLookupBuilders,
CreateComparer(rightPartitionedStream.KeyComparer), outputRecipient, partitionCount, cancellationToken);
}
else
{
PartitionedStream <Pair <TRightInput, TKey>, int> rePartitionedRightStream = ExchangeUtilities.HashRepartition(
rightPartitionedStream, _rightKeySelector, _keyComparer, null, cancellationToken);
HashLookupBuilder <IEnumerable <TRightInput>, int, TKey>[] rightLookupBuilders =
new HashLookupBuilder <IEnumerable <TRightInput>, int, TKey> [partitionCount];
for (int i = 0; i < partitionCount; i++)
{
rightLookupBuilders[i] = new GroupJoinHashLookupBuilder <TRightInput, int, TKey>(
rePartitionedRightStream[i], _keyComparer);
}
WrapPartitionedStreamHelper <TLeftKey, int>(leftHashStream, rightLookupBuilders,
null, outputRecipient, partitionCount, cancellationToken);
}
}
