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 (sharding_key)
        {
            auto sharding_expr = buildShardingKeyExpression(sharding_key, context, args.columns.getAllPhysical(), true);
            const Block & block = sharding_expr->getSampleBlock();
            if (block.columns() != 1)
                throw Exception("Sharding expression must return exactly one column", ErrorCodes::INCORRECT_NUMBER_OF_COLUMNS);
            auto type = block.getByPosition(0).type;
            if (!type->isValueRepresentedByInteger())
                throw Exception("Sharding expression has type " + type->getName() +
                    ", but should be one of integer type", ErrorCodes::TYPE_MISMATCH);
        }
        
        DistributedSettings distributed_settings;
        if (args.storage_def->settings)
        {
            distributed_settings.loadFromQuery(*args.storage_def);
        }
        if (distributed_settings.max_delay_to_insert < 1)
            throw Exception(ErrorCodes::ARGUMENT_OUT_OF_BOUND,
                "max_delay_to_insert cannot be less then 1");
        if (distributed_settings.bytes_to_throw_insert && distributed_settings.bytes_to_delay_insert &&
            distributed_settings.bytes_to_throw_insert <= distributed_settings.bytes_to_delay_insert)
        {
            throw Exception(ErrorCodes::ARGUMENT_OUT_OF_BOUND,
                "bytes_to_throw_insert cannot be less or equal to bytes_to_delay_insert (since it is handled first)");
        }
        
        if (!distributed_settings.monitor_batch_inserts.changed)