21.2:

```
milovidov-desktop :) SELECT CAST(1111111111.222 AS DateTime64(3))

SELECT cast(1111111111.222, 'DateTime64(3)')

Query id: d10c8623-5c74-4a38-b535-a99f6af4d28d

┌─cast(1111111111.222, 'DateTime64(3)')─┐
│               2005-03-18 04:58:31.222 │
└───────────────────────────────────────┘
```

master:

```
milovidov-desktop :) SELECT CAST(1111111111.222 AS DateTime64(3))

SELECT cast(1111111111.222, 'DateTime64(3)')

Query id: cb4af967-a4ae-4df5-89ba-234d68675f93

┌─cast(1111111111.222, 'DateTime64(3)')─┐
│               2005-03-18 04:58:31.000 │
└───────────────────────────────────────┘
```
{
        writeText(x, type->getScale(), wb);
    }
};
template <typename FieldType, typename Name>
struct ConvertImpl<DataTypeEnum<FieldType>, DataTypeNumber<FieldType>, Name, ConvertDefaultBehaviorTag>
{
    static ColumnPtr execute(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t )
    {
        return arguments[0].column;
    }
};
template <typename FromDataType, typename Name>
struct ConvertImpl<FromDataType, std::enable_if_t<!std::is_same_v<FromDataType, DataTypeString>, DataTypeString>, Name, ConvertDefaultBehaviorTag>
{
    using FromFieldType = typename FromDataType::FieldType;
    using ColVecType = std::conditional_t<IsDecimalNumber<FromFieldType>, ColumnDecimal<FromFieldType>, ColumnVector<FromFieldType>>;
    static ColumnPtr execute(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t )
    {
        const auto & col_with_type_and_name = arguments[0];
        const auto & type = static_cast<const FromDataType &>(*col_with_type_and_name.type);
        const DateLUTImpl * time_zone = nullptr;
        
        if constexpr (std::is_same_v<FromDataType, DataTypeDateTime> || std::is_same_v<FromDataType, DataTypeDateTime64>)
            time_zone = &extractTimeZoneFromFunctionArguments(arguments, 1, 0);
        if (const auto col_from = checkAndGetColumn<ColVecType>(col_with_type_and_name.column.get()))
        {
            auto col_to = ColumnString::create();
            const typename ColVecType::Container & vec_from = col_from->getData();
            ColumnString::Chars & data_to = col_to->getChars();