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 │
└───────────────────────────────────────┘
```
{
                            if (!isFinite(vec_from[i]))
                            {
                                if constexpr (std::is_same_v<Additions, AccurateOrNullConvertStrategyAdditions>)
                                {
                                    vec_to[i] = 0;
                                    (*vec_null_map_to)[i] = true;
                                    continue;
                                }
                                else
                                    throw Exception("Unexpected inf or nan to integer conversion", ErrorCodes::CANNOT_CONVERT_TYPE);
                            }
                        }
                        if constexpr (std::is_same_v<Additions, AccurateOrNullConvertStrategyAdditions>
                                || std::is_same_v<Additions, AccurateConvertStrategyAdditions>)
                        {
                            bool convert_result = accurate::convertNumeric(vec_from[i], vec_to[i]);
                            if (!convert_result)
                            {
                                if (std::is_same_v<Additions, AccurateOrNullConvertStrategyAdditions>)
                                {
                                    vec_to[i] = 0;
                                    (*vec_null_map_to)[i] = true;
                                }
                                else
                                {
                                    throw Exception(
                                        "Value in column " + named_from.column->getName() + " cannot be safely converted into type "
                                            + result_type->getName(),
                                        ErrorCodes::CANNOT_CONVERT_TYPE);