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'。
if (to_stage == QueryProcessingStage::WithMergeableState)
        return QueryProcessingStage::WithMergeableState;
    
    
    if (nodes == 1)
    {
        
        
        
        
        
        return std::max(to_stage, QueryProcessingStage::Complete);
    }
    else if (nodes == 0)
    {
        
        
        
        return QueryProcessingStage::FetchColumns;
    }
    auto optimized_stage = getOptimizedQueryProcessingStage(query_info, settings);
    if (optimized_stage)
    {
        if (*optimized_stage == QueryProcessingStage::Complete)
            return std::min(to_stage, *optimized_stage);
        return *optimized_stage;
    }
    return QueryProcessingStage::WithMergeableState;
}
std::optional<QueryProcessingStage::Enum> StorageDistributed::getOptimizedQueryProcessingStage(const SelectQueryInfo & query_info, const Settings & settings) const