presto-main/src/main/java/io/prestosql/operator/PartitionedLookupSource.java/PartitionedLookupSource/appendTo
class PartitionedLookupSource:    @Override
    public void appendTo(long partitionedJoinPosition, PageBuilder pageBuilder, int outputChannelOffset)
    {
        int partition = decodePartition(partitionedJoinPosition);
        int joinPosition = decodeJoinPosition(partitionedJoinPosition);
        lookupSources[partition].appendTo(joinPosition, pageBuilder, outputChannelOffset);
        if (outerPositionTracker != null) {
            outerPositionTracker.positionVisited(partition, joinPosition);
        }
    }