void npoint_mlpack::UnorderedMultiMatcher::ComputeBaseCase(NptNode* nodeA,
NptNode* nodeB,
std::vector<NptNode*>& nodeC_list,
PartialResult& result)
{
std::vector<NptNode*> node_list(3);
node_list[0] = nodeA;
node_list[1] = nodeB;
for (unsigned int i = 0; i < nodeC_list.size(); i++)
{
node_list[2] = nodeC_list[i];
NodeTuple this_tuple(node_list);
ComputeBaseCase(this_tuple, result);
}
}
/**
* @brief Advance the row iterator until value changes in terms of the join
* clauses
* @return the end row number, [start_row, end_row) are the rows of the same
* value
* if the end_row == start_row, the subset is empty
*/
size_t MergeJoinExecutor::Advance(LogicalTile *tile, size_t start_row,
bool is_left) {
size_t end_row = start_row + 1;
size_t this_row = start_row;
size_t tuple_count = tile->GetTupleCount();
if (start_row >= tuple_count) return start_row;
while (end_row < tuple_count) {
expression::ContainerTuple<executor::LogicalTile> this_tuple(tile,
this_row);
expression::ContainerTuple<executor::LogicalTile> next_tuple(tile,
end_row);
bool diff = false;
for (auto &clause : *join_clauses_) {
// Go through each join clauses
auto expr = is_left ? clause.left_.get() : clause.right_.get();
peloton::Value this_value =
expr->Evaluate(&this_tuple, &this_tuple, executor_context_);
peloton::Value next_value =
expr->Evaluate(&next_tuple, &next_tuple, executor_context_);
if (this_value.Compare(next_value) != 0) {
diff = true;
break;
}
}
if (diff) {
break;
}
// the two tuples are the same, we advance by 1
this_row = end_row;
end_row++;
}
LOG_TRACE("Advanced %s with subset size %lu ", is_left ? "left" : "right",
end_row - start_row);
return end_row;
}
