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 

zkutil::ZooKeeperPtr & zookeeper, String part_name, LogEntry & entry, bool detach, bool throw_if_noop)
{
    LOG_TRACE(log, "Will try to insert a log entry to DROP_RANGE for part: " + part_name);
    auto part_info = MergeTreePartInfo::fromPartName(part_name, format_version);
    while (true)
    {
        ReplicatedMergeTreeMergePredicate merge_pred = queue.getMergePredicate(zookeeper);
        auto part = getPartIfExists(part_info, {MergeTreeDataPartState::Committed});
        if (!part)
        {
            if (throw_if_noop)
                throw Exception("Part " + part_name + " not found locally, won't try to drop it.", ErrorCodes::NO_SUCH_DATA_PART);
            return false;
        }
        if (merge_pred.hasDropRange(part->info))
        {
            if (throw_if_noop)
                throw Exception("Already has DROP RANGE for part " + part_name + " in queue.", ErrorCodes::PART_IS_TEMPORARILY_LOCKED);
            return false;
        }
        
        
        if (partIsAssignedToBackgroundOperation(part))