Class HashPartitions

be/src/exec/partitioned-hash-join-builder.h:395–421

  /// Represents a set of hash partitions to be handed off to the probe side.
  struct HashPartitions {
    HashPartitions() { Reset(); }
    HashPartitions(int level,
        const std::vector<std::unique_ptr<PhjBuilderPartition>>* hash_partitions,
        bool non_empty_build)
      : level(level),
        hash_partitions(hash_partitions),
        non_empty_build(non_empty_build) {}

    void Reset() {
      level = -1;
      hash_partitions = nullptr;
      non_empty_build = false;
    }

    // The partitioning level of this set of partitions. -1 indicates that this is
    // invalid.
    int level;

    // The current set of hash partitions. Always contains PARTITION_FANOUT partitions.
    // The partitions may be in-memory, spilled, or closed. Valid until
    // DoneProbingHashPartitions() is called.
    const std::vector<std::unique_ptr<PhjBuilderPartition>>* hash_partitions;

    // True iff the build side had at least one row in a partition.
    bool non_empty_build;
  };

  /// Get hash partitions and reservation for the initial partitioning of the probe
  /// side. Only valid to call once per PartitionedHashJoinNode when in state