Method writeTempProjectionPart

src/Storages/MergeTree/MergeTreeDataWriter.cpp:737–765

}

MergeTreeMetaBase::MutableDataPartPtr MergeTreeDataWriter::writeTempProjectionPart(
    MergeTreeMetaBase & data,
    Poco::Logger * log,
    Block block,
    const ProjectionDescription & projection,
    const IMergeTreeDataPart * parent_part,
    size_t block_num,
    IStorage::StorageLocation write_location)
{
    /// Size of part would not be greater than block.bytes() + epsilon
    size_t expected_size = block.bytes();

    // just check if there is enough space on parent volume
    ReservationPtr reservation = data.reserveSpace(expected_size, parent_part->volume);

    String part_name = fmt::format("{}_{}", projection.name, block_num);
    MergeTreePartInfo new_part_info("all", 0, 0, 0);
    auto new_data_part = data.createPart(
        part_name,
        data.choosePartType(expected_size, block.rows()),
        new_part_info,
        parent_part->volume,
        "tmp_insert_" + part_name + ".proj",
        parent_part,
        write_location);
    new_data_part->is_temp = true; // It's part for merge

    return writeProjectionPartImpl(data, log, block, projection.metadata, std::move(new_data_part));
}

}