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'。
StorageMetadataPtr metadata_snapshot;
    void insertIntoBuffer(const Block & block, StorageBuffer::Buffer & buffer)
    {
        time_t current_time = time(nullptr);
        
        Block sorted_block = block.sortColumns();
        if (!buffer.data)
        {
            buffer.data = sorted_block.cloneEmpty();
            storage.total_writes.rows += buffer.data.rows();
            storage.total_writes.bytes += buffer.data.allocatedBytes();
        }
        else if (storage.checkThresholds(buffer, true, current_time, sorted_block.rows(), sorted_block.bytes()))
        {
            /** If, after inserting the buffer, the constraints are exceeded, then we will reset the buffer.
              * This also protects against unlimited consumption of RAM, since if it is impossible to write to the table,
              *  an exception will be thrown, and new data will not be added to the buffer.
              */
            storage.flushBuffer(buffer, false , true );
        }
        if (!buffer.first_write_time)
            buffer.first_write_time = current_time;
        size_t old_rows = buffer.data.rows();
        size_t old_bytes = buffer.data.allocatedBytes();
        appendBlock(sorted_block, buffer.data);
        storage.total_writes.rows += (buffer.data.rows() - old_rows);
        storage.total_writes.bytes += (buffer.data.allocatedBytes() - old_bytes);
    }
};
SinkToStoragePtr StorageBuffer::write(const ASTPtr & , const StorageMetadataPtr & metadata_snapshot, ContextPtr )