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::optional<UInt64> underlying_rows;
    auto underlying = DatabaseCatalog::instance().tryGetTable(destination_id, getContext());
    if (underlying)
        underlying_rows = underlying->totalRows(settings);
    if (!underlying_rows)
        return underlying_rows;
    return total_writes.rows + *underlying_rows;
}
std::optional<UInt64> StorageBuffer::totalBytes(const Settings & ) const
{
    return total_writes.bytes;
}
void StorageBuffer::alter(const AlterCommands & params, ContextPtr local_context, AlterLockHolder &)