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 (query_info.query->as<ASTSelectQuery>()->sampleSize() && !storage->supportsSampling())
            throw Exception("Illegal SAMPLE: table doesn't support sampling", ErrorCodes::SAMPLING_NOT_SUPPORTED);
        Aliases aliases;
        auto storage_metadata_snapshot = storage->getInMemoryMetadataPtr();
        auto storage_columns = storage_metadata_snapshot->getColumns();
        if (processed_stage == QueryProcessingStage::FetchColumns && !storage_columns.getAliases().empty())
        {
            auto syntax_result = TreeRewriter(local_context).analyzeSelect(query_info.query, TreeRewriterResult({}, storage, storage_metadata_snapshot));
            ASTPtr required_columns_expr_list = std::make_shared<ASTExpressionList>();
            ASTPtr column_expr;
            for (const auto & column : real_column_names)
            {
                const auto column_default = storage_columns.getDefault(column);
                bool is_alias = column_default && column_default->kind == ColumnDefaultKind::Alias;
                if (is_alias)
                {
                    column_expr = column_default->expression->clone();
                    replaceAliasColumnsInQuery(column_expr, storage_metadata_snapshot->getColumns(),
                                               syntax_result->array_join_result_to_source, local_context);
                    auto column_description = storage_columns.get(column);
                    column_expr = addTypeConversionToAST(std::move(column_expr), column_description.type->getName(),
                                                         storage_metadata_snapshot->getColumns().getAll(), local_context);
                    column_expr = setAlias(column_expr, column);
                    auto type = sample_block.getByName(column).type;
                    aliases.push_back({ .name = column, .type = type, .expression = column_expr->clone() });
                }
                else
                    column_expr = std::make_shared<ASTIdentifier>(column);
                required_columns_expr_list->children.emplace_back(std::move(column_expr));