#27685
has_output = !output_chunk.empty();
    }
    else
    {
        if (!non_joined_blocks)
        {
            if (!finish_counter || !finish_counter->isLast())
            {
                process_non_joined = false;
                return;
            }
            non_joined_blocks = join->getNonJoinedBlocks(outputs.front().getHeader(), max_block_size);
            if (!non_joined_blocks)
            {
                process_non_joined = false;
                return;
            }
        }
        Block block = non_joined_blocks->read();
        if (!block)
        {
            process_non_joined = false;
            return;
        }
        auto rows = block.rows();
        output_chunk.setColumns(block.getColumns(), rows);
        has_output = true;
    }
}
void JoiningTransform::transform(Chunk & chunk)