Method JoinBenchmark

cpp/src/arrow/acero/hash_join_benchmark.cc:64–183

class JoinBenchmark {
 public:
  explicit JoinBenchmark(BenchmarkSettings& settings) {
    SchemaBuilder l_schema_builder, r_schema_builder;
    std::vector<FieldRef> left_keys, right_keys;
    std::vector<JoinKeyCmp> key_cmp;
    for (size_t i = 0; i < settings.key_types.size(); i++) {
      std::string l_name = "lk" + std::to_string(i);
      std::string r_name = "rk" + std::to_string(i);

      // For integers, selectivity is the proportion of the build interval that overlaps
      // with the probe interval
      uint64_t num_build_rows = settings.num_build_batches * settings.batch_size;

      uint64_t min_build_value = 0;
      uint64_t max_build_value =
          static_cast<uint64_t>(num_build_rows * settings.cardinality);

      uint64_t min_probe_value =
          static_cast<uint64_t>((1.0 - settings.selectivity) * max_build_value);
      uint64_t max_probe_value = min_probe_value + max_build_value;

      std::unordered_map<std::string, std::string> build_metadata;
      build_metadata["null_probability"] = std::to_string(settings.null_percentage);
      build_metadata["min"] = std::to_string(min_build_value);
      build_metadata["max"] = std::to_string(max_build_value);
      build_metadata["min_length"] = std::to_string(settings.var_length_min);
      build_metadata["max_length"] = std::to_string(settings.var_length_max);

      std::unordered_map<std::string, std::string> probe_metadata;
      probe_metadata["null_probability"] = std::to_string(settings.null_percentage);
      probe_metadata["min"] = std::to_string(min_probe_value);
      probe_metadata["max"] = std::to_string(max_probe_value);

      auto l_field =
          field(l_name, settings.key_types[i], key_value_metadata(probe_metadata));
      auto r_field =
          field(r_name, settings.key_types[i], key_value_metadata(build_metadata));

      DCHECK_OK(l_schema_builder.AddField(l_field));
      DCHECK_OK(r_schema_builder.AddField(r_field));

      left_keys.push_back(FieldRef(l_name));
      right_keys.push_back(FieldRef(r_name));
      key_cmp.push_back(JoinKeyCmp::EQ);
    }

    for (size_t i = 0; i < settings.probe_payload_types.size(); i++) {
      std::string name = "lp" + std::to_string(i);
      DCHECK_OK(l_schema_builder.AddField(field(name, settings.probe_payload_types[i])));
    }

    for (size_t i = 0; i < settings.build_payload_types.size(); i++) {
      std::string name = "rp" + std::to_string(i);
      DCHECK_OK(r_schema_builder.AddField(field(name, settings.build_payload_types[i])));
    }

    auto l_schema = *l_schema_builder.Finish();
    auto r_schema = *r_schema_builder.Finish();