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'。
std::this_thread::sleep_for(std::chrono::milliseconds(step_ms));
        } while (*totalBytes(getContext()->getSettingsRef()) > distributed_settings.bytes_to_delay_insert && delayed_ms < distributed_settings.max_delay_to_insert*1000);
        ProfileEvents::increment(ProfileEvents::DistributedDelayedInserts);
        ProfileEvents::increment(ProfileEvents::DistributedDelayedInsertsMilliseconds, delayed_ms);
        UInt64 new_total_bytes = *totalBytes(getContext()->getSettingsRef());
        LOG_INFO(log, "Too many bytes pending for async INSERT: was {}, now {}, INSERT was delayed to {} ms",
            formatReadableSizeWithBinarySuffix(total_bytes),
            formatReadableSizeWithBinarySuffix(new_total_bytes),
            delayed_ms);
        if (new_total_bytes > distributed_settings.bytes_to_delay_insert)
        {
            ProfileEvents::increment(ProfileEvents::DistributedRejectedInserts);
            throw Exception(ErrorCodes::DISTRIBUTED_TOO_MANY_PENDING_BYTES,
                "Too many bytes pending for async INSERT: {} (bytes_to_delay_insert={})",
                formatReadableSizeWithBinarySuffix(new_total_bytes),
                formatReadableSizeWithBinarySuffix(distributed_settings.bytes_to_delay_insert));
        }
    }
}
void registerStorageDistributed(StorageFactory & factory)
{
    factory.registerStorage("Distributed", [](const StorageFactory::Arguments & args)
    {
        /** Arguments of engine is following:
          * - name of cluster in configuration;
          * - name of remote database;
          * - name of remote table;
          * - policy to store data in;
          *
          * Remote database may be specified in following form: