Method genCrossProductSingleBuildVector

bolt/exec/NestedLoopJoinProbe.cpp:635–690

}

RowVectorPtr NestedLoopJoinProbe::genCrossProductSingleBuildVector(
    const RowVectorPtr& buildVector,
    const RowTypePtr& outputType,
    const std::vector<IdentityProjection>& probeProjections,
    const std::vector<IdentityProjection>& buildProjections) {
  BOLT_CHECK(isSingleBuildVector());
  std::vector<VectorPtr> projectedChildren(outputType->size());
  const auto buildRowCount = buildVector->size();

  // Calculate how many probe rows we can cover without exceeding
  // outputBatchSize_.
  if (buildRowCount > outputBatchSize_) {
    probeRowCount_ = 1;
  } else {
    probeRowCount_ = std::min(
        static_cast<vector_size_t>(outputBatchSize_ / buildRowCount),
        input_->size() - probeRow_);
  }
  const size_t numOutputRows = probeRowCount_ * buildRowCount;

  // Generate probe dictionary indices.
  auto rawProbeIndices =
      initializeRowNumberMapping(probeIndices_, numOutputRows, pool());
  for (auto i = 0; i < probeRowCount_; ++i) {
    std::fill(
        rawProbeIndices.begin() + i * buildRowCount,
        rawProbeIndices.begin() + (i + 1) * buildRowCount,
        probeRow_ + i);
  }

  // Generate build dictionary indices.
  auto rawBuildIndices_ =
      initializeRowNumberMapping(buildIndices_, numOutputRows, pool());
  for (auto i = 0; i < probeRowCount_; ++i) {
    std::iota(
        rawBuildIndices_.begin() + i * buildRowCount,
        rawBuildIndices_.begin() + (i + 1) * buildRowCount,
        0);
  }

  projectChildren(
      projectedChildren,
      input_,
      probeProjections,
      numOutputRows,
      probeIndices_);
  projectChildren(
      projectedChildren,
      buildVector,
      buildProjections,
      numOutputRows,
      buildIndices_);

  return std::make_shared<RowVector>(
      pool(), outputType, nullptr, numOutputRows, std::move(projectedChildren));
}

RowVectorPtr NestedLoopJoinProbe::genCrossProductMultipleBuildVectors(