https://clickhouse-test-reports.s3.yandex.net/17375/99073c26ee2692f8efe2ab14b2d8ae0fd813b80e/fuzzer/fuzzer.log

```
SELECT
    k,
    topK(v)
FROM 
(
    SELECT
        number % 7 AS k,
        arrayMap(x -> arrayMap(x -> if(x = 0, NULL, toString(x)), range(x)), range(intDiv(number, 1))) AS v
    FROM system.numbers
    LIMIT 257
)
GROUP BY k
ORDER BY k ASC
```
{
        return *this;
    }
};
/** Compile-time interface for cell of the hash table.
  * Different cell types are used to implement different hash tables.
  * The cell must contain a key.
  * It can also contain a value and arbitrary additional data
  *  (example: the stored hash value; version number for ClearableHashMap).
  */
template <typename Key, typename Hash, typename TState = HashTableNoState>
struct HashTableCell
{
    using State = TState;
    using key_type = Key;
    using value_type = Key;
    using mapped_type = VoidMapped;
    Key key;
    HashTableCell() {}
    
    HashTableCell(const Key & key_, const State &) : key(key_) {}
    
    const Key & getKey() const { return key; }