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 │
└───────────────────────────────────────┘
```
}
                parsed = parsed && isAllRead(read_buffer);
                if (!parsed)
                    vec_to[i] = static_cast<typename ToDataType::FieldType>(0);
                if constexpr (exception_mode == ConvertFromStringExceptionMode::Null)
                    (*vec_null_map_to)[i] = !parsed;
            }
            current_offset = next_offset;
        }
        if constexpr (exception_mode == ConvertFromStringExceptionMode::Null)
            return ColumnNullable::create(std::move(col_to), std::move(col_null_map_to));
        else
            return col_to;
    }
};
template <typename ToDataType, typename Name>
struct ConvertImpl<std::enable_if_t<!std::is_same_v<ToDataType, DataTypeString>, DataTypeString>, ToDataType, Name, ConvertDefaultBehaviorTag>
    : ConvertThroughParsing<DataTypeString, ToDataType, Name, ConvertFromStringExceptionMode::Throw, ConvertFromStringParsingMode::Normal> {};
template <typename ToDataType, typename Name>
struct ConvertImpl<std::enable_if_t<!std::is_same_v<ToDataType, DataTypeFixedString>, DataTypeFixedString>, ToDataType, Name, ConvertDefaultBehaviorTag>
    : ConvertThroughParsing<DataTypeFixedString, ToDataType, Name, ConvertFromStringExceptionMode::Throw, ConvertFromStringParsingMode::Normal> {};
template <typename ToDataType, typename Name>
struct ConvertImpl<std::enable_if_t<!std::is_same_v<ToDataType, DataTypeString>, DataTypeString>, ToDataType, Name, ConvertReturnNullOnErrorTag>
    : ConvertThroughParsing<DataTypeString, ToDataType, Name, ConvertFromStringExceptionMode::Null, ConvertFromStringParsingMode::Normal> {};
template <typename ToDataType, typename Name>
struct ConvertImpl<std::enable_if_t<!std::is_same_v<ToDataType, DataTypeFixedString>, DataTypeFixedString>, ToDataType, Name, ConvertReturnNullOnErrorTag>
    : ConvertThroughParsing<DataTypeFixedString, ToDataType, Name, ConvertFromStringExceptionMode::Null, ConvertFromStringParsingMode::Normal> {};
struct ConvertImplGenericFromString
{
    static ColumnPtr execute(ColumnsWithTypeAndName & arguments, const DataTypePtr & result_type)