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 

{
            return std::forward_as_tuple(static_cast<UInt8>(lhs.state), lhs.partition_id)
                   < std::forward_as_tuple(static_cast<UInt8>(rhs.state), rhs.info.partition_id);
        }
    };
    using DataParts = std::set<DataPartPtr, LessDataPart>;
    using DataPartsVector = std::vector<DataPartPtr>;
    using DataPartsLock = std::unique_lock<std::mutex>;
    DataPartsLock lockParts() const { return DataPartsLock(data_parts_mutex); }
    MergeTreeDataPartType choosePartType(size_t bytes_uncompressed, size_t rows_count) const;
    MergeTreeDataPartType choosePartTypeOnDisk(size_t bytes_uncompressed, size_t rows_count) const;
    
    MutableDataPartPtr createPart(const String & name,
        MergeTreeDataPartType type, const MergeTreePartInfo & part_info,
        const VolumePtr & volume, const String & relative_path, const IMergeTreeDataPart * parent_part = nullptr) const;
    
    
    MutableDataPartPtr createPart(const String & name,
        const VolumePtr & volume, const String & relative_path, const IMergeTreeDataPart * parent_part = nullptr) const;
    MutableDataPartPtr createPart(const String & name, const MergeTreePartInfo & part_info,
        const VolumePtr & volume, const String & relative_path, const IMergeTreeDataPart * parent_part = nullptr) const;
    
    
    
    
    
    class Transaction : private boost::noncopyable
    {
    public:
        Transaction(MergeTreeData & data_) : data(data_) {}