Method readExecute

src/Processors/Transforms/JoiningTransform.cpp:240–261

}

Block JoiningTransform::readExecute(Chunk & chunk)
{
    if (!join_result)
    {
        Block block = inputs.front().getHeader().cloneWithColumns(chunk.detachColumns());
        ProfileEvents::increment(ProfileEvents::JoinProbeTableRowCount, block.rows());
        join_result = join->joinBlock(std::move(block));
    }

    auto data = join_result->next();
    if (data.is_last && data.next_block)
    {
        data.next_block->filterBySelector();
        auto next_block = std::move(*data.next_block).getSourceBlock();
        chunk.setColumns(next_block.getColumns(), next_block.rows());
    }

    if (data.is_last)
        join_result.reset();

    return std::move(data.block);
}

FillingRightJoinSideTransform::FillingRightJoinSideTransform(SharedHeader input_header, JoinPtr join_, FinishCounterPtr finish_counter_)
    : IProcessor({input_header}, {Block()}), join(std::move(join_)), finish_counter(std::move(finish_counter_))