接口方法把taos数据库对微秒级的支持强行改成了毫秒级

[lucienbao]

https://github.com/maikebing/Maikebing.EntityFrameworkCore.Taos/blob/85fc923a57f88ea3533628281af16f347296c460/src/Maikebing.Data.Taos/TaosDataReader.cs#L631

[lucienbao]

另外TaosCommand.cs 319行的写法也有问题，具体参见http://www.tdengine.com/cn/documentation/taos-sql 中“插入一条或多条记录”小节下方的“注意”小节的内容提示。

                        case TypeCode.DateTime:
                            //_endcommandtext = _endcommandtext.Replace(tp.ParameterName, $"{(long)((tp.Value as DateTime?).GetValueOrDefault().Subtract(new DateTime(1970, 1, 1, 0, 0, 0, 0)).TotalMilliseconds)}");
                            var t0 = tp.Value as DateTime?;
                            if (!t0.HasValue)
                            {
                                throw new ArgumentException($"InvalidArgumentOfDateTime{tp.Value}");
                            }
                            _endcommandtext = _endcommandtext.Replace(tp.ParameterName, $"'{t0.Value:yyyy-MM-dd HH:mm:ss.ffffff}'");
                            break;

[lucienbao]

在TaosDataReader 307行

   public virtual TimeSpan GetTimeSpan(int ordinal)
    {
        var val = Marshal.ReadInt64(GetValuePtr(ordinal));
        var _dateTimePrecision = (TSDB_TIME_PRECISION)TDengine.ResultPrecision(_taosResult);
        switch (_dateTimePrecision)
        {
         /*
         * ticks为100纳秒，必须乘以10才能达到微秒级的区分度
         * 1秒s    = 1000毫秒ms
         * 1毫秒ms = 1000微秒us
         * 1微秒us = 1000纳秒ns
         * 因此， 1毫秒ms = 1000000纳秒ns = 10000ticks
         */
            case TSDB_TIME_PRECISION.TSDB_TIME_PRECISION_NANO:
                return TimeSpan.FromTicks(val / 100);
            case TSDB_TIME_PRECISION.TSDB_TIME_PRECISION_MICRO:
                return TimeSpan.FromTicks(val * 10);
            case TSDB_TIME_PRECISION.TSDB_TIME_PRECISION_MILLI:
            default:
                return TimeSpan.FromTicks(val * 10000);
        }
        //if (_dateTimePrecision == TSDB_TIME_PRECISION.TSDB_TIME_PRECISION_MICRO)
        //{
        //    return TimeSpan.FromMilliseconds(val / 1000);
        //}
        //else
        //{
        //    return TimeSpan.FromMilliseconds(val);
        //}
    }

[lucienbao]

在TaosDataReader 648行

   private DateTime GetDateTimeFrom(IntPtr data)
    {
        var val = Marshal.ReadInt64(data);
        //double tsp;
        var _dateTimePrecision = (TSDB_TIME_PRECISION)TDengine.ResultPrecision(_taosResult);
        switch (_dateTimePrecision)
        {
            /*
            * ticks为100纳秒，必须乘以10才能达到微秒级的区分度
            * 1秒s    = 1000毫秒ms
            * 1毫秒ms = 1000微秒us
            * 1微秒us = 1000纳秒ns
            * 因此， 1毫秒ms = 1000000纳秒ns = 10000ticks
            */
            case TSDB_TIME_PRECISION.TSDB_TIME_PRECISION_NANO:
                val /= 100;
                break;
            case TSDB_TIME_PRECISION.TSDB_TIME_PRECISION_MICRO:
                val *= 10;
                break;
            case TSDB_TIME_PRECISION.TSDB_TIME_PRECISION_MILLI:
            default:
                val *= 10000;
                break;
        }
        //if (_dateTimePrecision == TSDB_TIME_PRECISION.TSDB_TIME_PRECISION_MICRO)
        //{
        //    tsp = (val / 1000);
        //}
        //else
        //{
        //    tsp = val;
        //}
        //if (tsp > _date_max_1970)
        //{
        //    //fix https://github.com/taosdata/TDengine/issues/3270
        //    tsp /= 1000;
        //}
        //var v9 = _dt1970.AddMilliseconds(tsp);
        var v9 = _dt1970.AddTicks(val);
        return v9.ToLocalTime();
    }

[maikebing]

已经修订。