**Describe the bug**

I have a table like:

```
CREATE TABLE test (
    time DateTime64(3)
    ...
) ENGINE = MergeTree()
PARTITION BY toStartOfInterval(time, INTERVAL 1 HOUR)
...
```

But when I search in `system.parts` it does not appear to have the `min/max` columns appropriately set?

```
partition:                             2020-06-01 01:00:00
min_date:                              1970-01-01
max_date:                              1970-01-01
min_time:                              1970-01-01 00:00:00
max_time:                              1970-01-01 00:00:00
```

I assume that if these were correctly set, doing a `select toStartOfInterval(time, interval 1 day), count()` type query would be pretty instant rather than trying to scan everything? I am guessing this is due to the `DateTime64` type in use?

Clickhouse 20.11.3.3

{
    auto policy = getStoragePolicy();
    if (ttl.destination_type == DataDestinationType::VOLUME)
    {
        for (const auto & disk : policy->getVolumeByName(ttl.destination_name)->getDisks())
            if (disk->getName() == part.volume->getDisk()->getName())
                return true;
    }
    else if (ttl.destination_type == DataDestinationType::DISK)
        return policy->getDiskByName(ttl.destination_name)->getName() == part.volume->getDisk()->getName();
    return false;
}
CompressionCodecPtr MergeTreeData::getCompressionCodecForPart(size_t part_size_compressed, const IMergeTreeDataPart::TTLInfos & ttl_infos, time_t current_time) const