I am reading clickhouse mutation code. In StorageMergeTree->selectPartsToMutate() function, there is a check 
`if (current_ast_elements + commands_size >= max_ast_elements)
                break;`

I think if there are many mutations then the check result will be true, so that it will skip the remaining mutations.
But the new part's mutation is set to the last one in mutation map, and it does not apply the remaining mutations actually.
`new_part_info.mutation = current_mutations_by_version.rbegin()->first;`

Then the new part will miss the remaining mutations in future mutation job.

I think it's wrong here. Am I right?

If it is right, I will submit a PR 

{
    
    StorageInMemoryMetadata new_metadata = getInMemoryMetadata();
    StorageInMemoryMetadata old_metadata = getInMemoryMetadata();
    const auto & settings = local_context->getSettingsRef();
    if (!settings.allow_non_metadata_alters)
    {
        auto mutation_commands = commands.getMutationCommands(new_metadata, settings.materialize_ttl_after_modify, getContext());
        if (!mutation_commands.empty())
            throw Exception(ErrorCodes::ALTER_OF_COLUMN_IS_FORBIDDEN, "The following alter commands: '{}' will modify data on disk, but setting `allow_non_metadata_alters` is disabled", queryToString(mutation_commands.ast()));
    }
    commands.apply(new_metadata, getContext());
    
    NameSet columns_alter_type_forbidden;
    
    
    NameSet columns_alter_type_metadata_only;
    
    NameSet columns_alter_type_check_safe_for_partition;
    if (old_metadata.hasPartitionKey())
    {
        
        auto partition_key_expr = old_metadata.getPartitionKey().expression;
        for (const auto & action : partition_key_expr->getActions())
        {
            for (const auto * child : action.node->children)
                columns_alter_type_forbidden.insert(child->result_name);