**Use case**
I'm using `ip_trie` on maxmind geoip databases. Given an IP address I want to find out what key was used (ie what network the IP comes under). But it seems it is not possible to look up the key field when using `dictGet`?

```
        <layout>
            <ip_trie/>
        </layout>
        <structure>
            <key>
                <attribute>
                    <name>network</name>
                    <type>String</type>
                </attribute>
            </key>
            <attribute>
                <name>geoname_id</name>
                <type>UInt32</type>
                <null_value>0</null_value>
            </attribute>
...
```

```
clickhouse :) select dictGet('geoip_city_blocks_ipv4', 'geoname_id', tuple(toUInt32(toIPv4('1.1.1.1')))) ;

┌─dictGet('geoip_city_blocks_ipv4', 'geoname_id', tuple(toUInt32(toIPv4('1.1.1.1'))))─┐
│                                                                             2077456 │
└─────────────────────────────────────────────────────────────────────────────────────┘

clickhouse :) select dictGet('geoip_city_blocks_ipv4', 'network', tuple(toUInt32(toIPv4('1.1.1.1')))) ;

Received exception from server (version 20.11.3):
Code: 36. DB::Exception: Received from localhost:9000. DB::Exception: No such attribute 'network': While processing dictGet('geoip_city_blocks_ipv4', 'network', tuple(toUInt32(toIPv4('1.1.1.1')))). 
```

{
    Attribute attr{type, {}, {}, {}};
    switch (type)
    {
        case AttributeUnderlyingType::utUInt8:
            createAttributeImpl<UInt8>(attr, null_value);
            break;
        case AttributeUnderlyingType::utUInt16:
            createAttributeImpl<UInt16>(attr, null_value);
            break;
        case AttributeUnderlyingType::utUInt32:
            createAttributeImpl<UInt32>(attr, null_value);
            break;
        case AttributeUnderlyingType::utUInt64:
            createAttributeImpl<UInt64>(attr, null_value);
            break;
        case AttributeUnderlyingType::utUInt128:
            createAttributeImpl<UInt128>(attr, null_value);
            break;
        case AttributeUnderlyingType::utInt8:
            createAttributeImpl<Int8>(attr, null_value);
            break;
        case AttributeUnderlyingType::utInt16:
            createAttributeImpl<Int16>(attr, null_value);
            break;
        case AttributeUnderlyingType::utInt32:
            createAttributeImpl<Int32>(attr, null_value);