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

Some times there are not output from requests.
{
    std::unordered_set<String> partition_ids;
    for (const auto & ast : asts)
        partition_ids.emplace(getPartitionIDFromQuery(ast, local_context));
    return partition_ids;
}
std::set<String> MergeTreeData::getPartitionIdsAffectedByCommands(
    const MutationCommands & commands, ContextPtr query_context) const
{
    std::set<String> affected_partition_ids;
    for (const auto & command : commands)
    {
        if (!command.partition)
        {
            affected_partition_ids.clear();
            break;
        }
        affected_partition_ids.insert(
            getPartitionIDFromQuery(command.partition, query_context)
        );
    }
    return affected_partition_ids;
}
MergeTreeData::DataPartsVector MergeTreeData::getDataPartsVectorForInternalUsage(