AST-based query fuzzer should randomly modify data types in CREATE TABLE queries, mostly by wrapping in Nullable, Array and LowCardinality.
{
    const auto type = field.getType();
    int type_index = -1;
    if (type == Field::Types::Int64
        || type == Field::Types::UInt64)
    {
        type_index = 0;
    }
    else if (type == Field::Types::Float64)
    {
        type_index = 1;
    }
    else if (type == Field::Types::Decimal32
             || type == Field::Types::Decimal64
             || type == Field::Types::Decimal128)
    {
        type_index = 2;
    }
    if (fuzz_rand() % 20 == 0)
    {
        return Null{};
    }
    if (type_index >= 0)
    {
        if (fuzz_rand() % 20 == 0)
        {