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 (!flush_handle)
        return;
    flush_handle->deactivate();
    try
    {
        optimize(nullptr , getInMemoryMetadataPtr(), {} , false , false , {}, getContext());
    }
    catch (...)
    {
        tryLogCurrentException(__PRETTY_FUNCTION__);
    }
}
/** NOTE If you do OPTIMIZE after insertion,
  * it does not guarantee, that all data will be in destination table at the time of next SELECT just after OPTIMIZE.
  *
  * Because in case if there was already running flushBuffer method,
  *  then call to flushBuffer inside OPTIMIZE will see empty buffer and return quickly,
  *  but at the same time, the already running flushBuffer method possibly is not finished,
  *  so next SELECT will observe missing data.
  *
  * This kind of race condition make very hard to implement proper tests.
  */
bool StorageBuffer::optimize(