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 

if (new_projections_str != current_metadata->projections.toString())
            future_metadata_in_zk.projections = new_projections_str;
        String new_constraints_str = future_metadata.constraints.toString();
        if (new_constraints_str != current_metadata->constraints.toString())
            future_metadata_in_zk.constraints = new_constraints_str;
        Coordination::Requests ops;
        size_t alter_path_idx = std::numeric_limits<size_t>::max();
        size_t mutation_path_idx = std::numeric_limits<size_t>::max();
        String new_metadata_str = future_metadata_in_zk.toString();
        ops.emplace_back(zkutil::makeSetRequest(fs::path(zookeeper_path) / "metadata", new_metadata_str, metadata_version));
        String new_columns_str = future_metadata.columns.toString();
        ops.emplace_back(zkutil::makeSetRequest(fs::path(zookeeper_path) / "columns", new_columns_str, -1));
        if (ast_to_str(current_metadata->settings_changes) != ast_to_str(future_metadata.settings_changes))
        {
            
            StorageInMemoryMetadata metadata_copy = *current_metadata;
            metadata_copy.settings_changes = future_metadata.settings_changes;
            changeSettings(metadata_copy.settings_changes, table_lock_holder);
            DatabaseCatalog::instance().getDatabase(table_id.database_name)->alterTable(query_context, table_id, metadata_copy);
        }
        
        
        int new_metadata_version = metadata_version + 1;
        alter_entry->type = LogEntry::ALTER_METADATA;
        alter_entry->source_replica = replica_name;
        alter_entry->metadata_str = new_metadata_str;
        alter_entry->columns_str = new_columns_str;
        alter_entry->alter_version = new_metadata_version;
        alter_entry->create_time = time(nullptr);
        auto maybe_mutation_commands = commands.getMutationCommands(