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

Some times there are not output from requests.
}
            break;
            case PartitionCommand::UNFREEZE_ALL_PARTITIONS:
            {
                auto lock = lockForShare(query_context->getCurrentQueryId(), query_context->getSettingsRef().lock_acquire_timeout);
                current_command_results = unfreezeAll(command.with_name, query_context, lock);
            }
            break;
            default:
                throw Exception("Uninitialized partition command", ErrorCodes::LOGICAL_ERROR);
        }
        for (auto & command_result : current_command_results)
            command_result.command_type = command.typeToString();
        result.insert(result.end(), current_command_results.begin(), current_command_results.end());
    }
    if (query_context->getSettingsRef().alter_partition_verbose_result)
        return convertCommandsResultToSource(result);
    return {};
}
void MergeTreeData::backupData(BackupEntriesCollector & backup_entries_collector, const String & data_path_in_backup, const std::optional<ASTs> & partitions)
{
    auto local_context = backup_entries_collector.getContext();
    DataPartsVector data_parts;
    if (partitions)
        data_parts = getVisibleDataPartsVectorInPartitions(local_context, getPartitionIDsFromQuery(*partitions, local_context));
    else
        data_parts = getVisibleDataPartsVector(local_context);
    backup_entries_collector.addBackupEntries(backupParts(data_parts, data_path_in_backup, local_context));
}
BackupEntries MergeTreeData::backupParts(const DataPartsVector & data_parts, const String & data_path_in_backup, const ContextPtr & local_context)