Method beginBuildMismatch

bolt/exec/NestedLoopJoinProbe.cpp:808–844

}

void NestedLoopJoinProbe::beginBuildMismatch() {
  BOLT_CHECK(needsBuildMismatch(joinType_));

  // Check the state of peer operators. Only the last driver (operator) running
  // this code will survive and move on to process build mismatches.
  std::vector<ContinuePromise> promises;
  std::vector<std::shared_ptr<Driver>> peers;
  if (!operatorCtx_->task()->allPeersFinished(
          planNodeId(), operatorCtx_->driver(), &future_, promises, peers)) {
    BOLT_CHECK(future_.valid());
    setState(ProbeOperatorState::kWaitForPeers);
    return;
  }

  lastProbe_ = true;

  // From now on, buildIndex_ is used to indexing into buildMismatched_
  BOLT_CHECK_EQ(buildIndex_, 0);

  // Colect and merge the build mismatch selectivity vectors from all peers.
  for (auto& peer : peers) {
    auto* op = peer->findOperator(planNodeId());
    auto* probe = dynamic_cast<NestedLoopJoinProbe*>(op);
    BOLT_CHECK_NOT_NULL(probe);
    for (auto i = 0; i < buildMatched_.size(); ++i) {
      buildMatched_[i].select(probe->buildMatched_[i]);
      probeSideEmpty_ &= probe->probeSideEmpty_;
    }
  }
  peers.clear();
  for (auto& matched : buildMatched_) {
    matched.updateBounds();
  }
  for (auto& promise : promises) {
    promise.setValue();
  }
}

RowVectorPtr NestedLoopJoinProbe::getBuildMismatchedOutput(
    const RowVectorPtr& data,