**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

if (!new_part_info.isDisjoint((*prev)->info))
                throw Exception("Part " + new_part_name + " intersects previous part " + (*prev)->getNameWithState() +
                    ". It is a bug.", ErrorCodes::LOGICAL_ERROR);
            break;
        }
        begin = prev;
    }
    
    DataPartIteratorByStateAndInfo end = it_middle;
    while (end != committed_parts_range.end())
    {
        if ((*end)->info == new_part_info)
            throw Exception("Unexpected duplicate part " + (*end)->getNameWithState() + ". It is a bug.", ErrorCodes::LOGICAL_ERROR);
        if (!new_part_info.contains((*end)->info))
        {
            if ((*end)->info.contains(new_part_info))
            {
                out_covering_part = *end;
                return {};
            }
            if (!new_part_info.isDisjoint((*end)->info))
                throw Exception("Part " + new_part_name + " intersects next part " + (*end)->getNameWithState() +
                    ". It is a bug.", ErrorCodes::LOGICAL_ERROR);
            break;
        }
        ++end;
    }
    return DataPartsVector{begin, end};
}
bool MergeTreeData::renameTempPartAndAdd(MutableDataPartPtr & part, SimpleIncrement * increment, Transaction * out_transaction)