Change the table comment after created the table is not supported now?
Like mysql : ALTER TABLE [tableName] COMMNET [comment]; 
The sql "ALTER TABLE `system`.tables UPDATE Comment='test' WHERE NAME='t1';" also not supported!!!
My version is '21.9.4.35'。
}
            pipe_from_buffers.addSimpleTransform([&](const Block & header)
            {
                return std::make_shared<FilterTransform>(
                        header,
                        std::make_shared<ExpressionActions>(query_info.prewhere_info->prewhere_actions, actions_settings),
                        query_info.prewhere_info->prewhere_column_name,
                        query_info.prewhere_info->remove_prewhere_column);
            });
        }
        auto read_from_buffers = std::make_unique<ReadFromPreparedSource>(std::move(pipe_from_buffers));
        read_from_buffers->setStepDescription("Read from buffers of Buffer table");
        buffers_plan.addStep(std::move(read_from_buffers));
    }
    if (!query_plan.isInitialized())
    {
        query_plan = std::move(buffers_plan);
        return;
    }
    auto result_header = buffers_plan.getCurrentDataStream().header;
    
    if (!blocksHaveEqualStructure(query_plan.getCurrentDataStream().header, result_header))
    {
        auto convert_actions_dag = ActionsDAG::makeConvertingActions(
                query_plan.getCurrentDataStream().header.getColumnsWithTypeAndName(),
                result_header.getColumnsWithTypeAndName(),
                ActionsDAG::MatchColumnsMode::Name);
        auto converting = std::make_unique<ExpressionStep>(query_plan.getCurrentDataStream(), convert_actions_dag);
        query_plan.addStep(std::move(converting));
    }