```
$ ~/arc/build/clickhouse/programs/clickhouse client
ClickHouse client version 21.2.1.1-arcadia.
Connecting to localhost:9000 as user default.
Connected to ClickHouse server version 21.2.1 revision 54447.

max42-dev.sas.yp-c.yandex.net :) create table t(a Tuple(UInt8, UInt8)) engine = Log()

CREATE TABLE t
(
    `a` Tuple(UInt8, UInt8)
)
ENGINE = Log

Query id: b49dbb5d-d2a9-4c99-b90e-00c60edf2103

Ok.

0 rows in set. Elapsed: 0.005 sec. 

max42-dev.sas.yp-c.yandex.net :) insert into t values ((NULL, 42))

INSERT INTO t VALUES

Query id: 318d6f3e-f3bc-467c-85ff-62da908230dd

Logical error: 'Unexpected literal type inside Array: Nothing. It's a bug'.
Aborted (core dumped)
```

This is CH similar to one from Arcadia r7788360 (~fresh master version from GH).

(you don't have to strictly follow this form)

{
    return Tuple(ext::map<Tuple>(elems, [] (const DataTypePtr & elem) { return elem->getDefault(); }));
}
void DataTypeTuple::insertDefaultInto(IColumn & column) const
{
    addElementSafe(elems, column, [&]
    {
        for (const auto & i : ext::range(0, ext::size(elems)))
            elems[i]->insertDefaultInto(extractElementColumn(column, i));
    });
}
bool DataTypeTuple::equals(const IDataType & rhs) const
{
    if (typeid(rhs) != typeid(*this))
        return false;
    const DataTypeTuple & rhs_tuple = static_cast<const DataTypeTuple &>(rhs);
    size_t size = elems.size();
    if (size != rhs_tuple.elems.size())
        return false;
    for (size_t i = 0; i < size; ++i)
        if (!elems[i]->equals(*rhs_tuple.elems[i]))
            return false;
    return true;
}
size_t DataTypeTuple::getPositionByName(const String & name) const