Statistics
https://play.clickhouse.com/play?user=play#c2VsZWN0IAp0b1N0YXJ0T2ZIb3VyKGNoZWNrX3N0YXJ0X3RpbWUpIGFzIGQsCmNvdW50KCksICBncm91cFVuaXFBcnJheShwdWxsX3JlcXVlc3RfbnVtYmVyKSwgIGFueShyZXBvcnRfdXJsKQpmcm9tIGNoZWNrcyB3aGVyZSAnMjAyMi0wNi0wMScgPD0gY2hlY2tfc3RhcnRfdGltZSBhbmQgdGVzdF9uYW1lIGxpa2UgJyUwMjQ5MV9wYXJ0X2xvZ19oYXNfdGFibGVfdXVpZCUnIGFuZCB0ZXN0X3N0YXR1cyBpbiAoJ0ZBSUwnLCAnRkxBS1knKSBncm91cCBieSBkIG9yZGVyIGJ5IGQgZGVzYw==

Some times there are not output from requests.
std::unordered_set<String> subdirs;
    for (const String & filename : filenames)
    {
        
        auto separator_pos = filename.rfind('/');
        if (separator_pos != String::npos)
        {
            String subdir = filename.substr(0, separator_pos);
            if (subdirs.emplace(subdir).second)
                disk->createDirectories(temp_part_dir / subdir);
        }
        
        if (filename.ends_with(IMergeTreeDataPart::TXN_VERSION_METADATA_FILE_NAME))
            continue;
        auto backup_entry = backup->readFile(part_path_in_backup_fs / filename);
        auto read_buffer = backup_entry->getReadBuffer();
        auto write_buffer = disk->writeFile(temp_part_dir / filename);
        copyData(*read_buffer, *write_buffer);
        reservation->update(reservation->getSize() - backup_entry->getSize());
    }
    auto single_disk_volume = std::make_shared<SingleDiskVolume>(disk->getName(), disk, 0);
    auto data_part_storage = std::make_shared<DataPartStorageOnDisk>(single_disk_volume, temp_part_dir.parent_path(), part_name);
    auto part = createPart(part_name, part_info, data_part_storage);
    part->version.setCreationTID(Tx::PrehistoricTID, nullptr);
    part->loadColumnsChecksumsIndexes(false, true);
    restored_parts_holder->addPart(part);
}
String MergeTreeData::getPartitionIDFromQuery(const ASTPtr & ast, ContextPtr local_context, DataPartsLock * acquired_lock) const