NULL float64 not working

[olliemoves]

I have downloaded the latest version of the driver with

go get github.com/Go-SQL-Driver/MySQL

I am not getting errors is I use sql.NullString when loading null values but I am still getting the error for sql.NullFloat64

sql: Scan error on column index 4: converting string "" to a float64: strconv.ParseFloat: parsing "": invalid syntax

Is there only support for null strings? or should this be working for null float64?

[julienschmidt]

Can you provide your table structure and your query string?
That would help me finding the problem.

[olliemoves]

Database struct

type PersonMetric struct {
    Id                int
    PersonId          int
    ActualDateTime    string //time.Time
    Weight            sql.NullFloat64
    BodyFatPercentage sql.NullFloat64
    SleepQuality      sql.NullFloat64
    SleepDuration     sql.NullFloat64
    OverallFeeling    sql.NullFloat64
    Comment           sql.NullString
}

Method

func (this *PersonMetricRepository) GetByPersonId(personId int) (*[]PersonMetric, error) {
    db := this.OpenDB()
    defer db.Close()
    rows, err := db.Query("SELECT Id, PersonId, ActualDateTime, Weight, BodyFatPercentage, SleepQuality, SleepDuration, OverallFeeling, Comment FROM PersonMetric WHERE PersonId=?;", personId)
    var list []PersonMetric
    if err == nil {
        for rows.Next() {
            var personMetric PersonMetric
            err := rows.Scan(&personMetric.Id, &personMetric.PersonId, &personMetric.ActualDateTime, &personMetric.Weight, &personMetric.BodyFatPercentage, &personMetric.SleepQuality, &personMetric.SleepDuration, &personMetric.OverallFeeling, &personMetric.Comment)
            if err != nil {
                return nil, err
            }
            list = append(list, personMetric)
        }
    }
    return &list, err
}

Table

CREATE TABLE `PersonMetric` (
  `Id` int(11) NOT NULL AUTO_INCREMENT,
  `PersonId` int(11) DEFAULT NULL,
  `ActualDateTime` datetime DEFAULT NULL,
  `Weight` float DEFAULT NULL,
  `BodyFatPercentage` float DEFAULT NULL,
  `SleepQuality` float DEFAULT NULL,
  `SleepDuration` float DEFAULT NULL,
  `OverallFeeling` float DEFAULT NULL,
  `Comment` text,
  PRIMARY KEY (`Id`)
) ENGINE=InnoDB AUTO_INCREMENT=116 DEFAULT CHARSET=latin1;

Data

INSERT INTO `PersonMetric` VALUES ('1', '2', '2011-10-22 00:00:00', '69.3', '10.3', '6', '9', '7', null);
INSERT INTO `PersonMetric` VALUES ('2', '2', '2011-10-23 00:00:00', '70.1', '9.6', '8', '9', '8', null);
INSERT INTO `PersonMetric` VALUES ('3', '2', '2011-10-24 00:00:00', '69.9', '9.5', '6', '8', '9', null);
INSERT INTO `PersonMetric` VALUES ('4', '2', '2011-11-05 00:00:00', '70.4', '9.6', '8', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('5', '2', '2011-11-17 00:00:00', '69.6', '9.1', '8', '7.5', '8', null);
INSERT INTO `PersonMetric` VALUES ('6', '2', '2011-11-25 00:00:00', '70.6', '9.6', '8', '7', '5', null);
INSERT INTO `PersonMetric` VALUES ('7', '2', '2011-12-21 00:00:00', '70.4', '9.4', '6', '6', '10', null);
INSERT INTO `PersonMetric` VALUES ('8', '2', '2012-01-03 00:00:00', '71.6', '10.1', '6', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('9', '2', '2012-01-11 00:00:00', '70.1', '9.6', '7', '8', '5', null);
INSERT INTO `PersonMetric` VALUES ('10', '2', '2012-01-12 00:00:00', '69.7', '9.4', '5', '7', '5', null);
INSERT INTO `PersonMetric` VALUES ('11', '2', '2012-01-26 00:00:00', '69.9', '9.8', '8', '8', '6', null);
INSERT INTO `PersonMetric` VALUES ('12', '2', '2011-10-25 00:00:00', '70.5', '11.5', '6', '7.5', '6', null);
INSERT INTO `PersonMetric` VALUES ('13', '2', '2011-10-26 00:00:00', '70.1', '9.5', '7', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('14', '2', '2011-10-27 00:00:00', '69.5', '9.5', '8', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('15', '2', '2011-10-28 00:00:00', '69.3', '9.5', '8', '9', '8', null);
INSERT INTO `PersonMetric` VALUES ('16', '2', '2011-10-29 00:00:00', '70.5', '11.5', '7', '9', '6', null);
INSERT INTO `PersonMetric` VALUES ('17', '2', '2011-10-30 00:00:00', '69.8', '9.9', '7', '9', '7', null);
INSERT INTO `PersonMetric` VALUES ('18', '2', '2011-07-20 00:00:00', '74.3', '11', '7', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('19', '2', '2011-11-01 00:00:00', '69.5', '9.5', '8', '9', '7', null);
INSERT INTO `PersonMetric` VALUES ('20', '2', '2011-09-30 00:00:00', '69.3', null, '5', '9', '7', null);
INSERT INTO `PersonMetric` VALUES ('21', '2', '2011-09-29 00:00:00', '69.7', null, '5', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('22', '2', '2011-09-15 00:00:00', '69.8', null, '7', '7.5', '7', null);
INSERT INTO `PersonMetric` VALUES ('23', '2', '2011-11-02 00:00:00', '70.5', '9.5', '8', '8', '6', null);
INSERT INTO `PersonMetric` VALUES ('24', '2', '2011-11-03 00:00:00', '69.6', '9.6', '6', '7', '6', null);
INSERT INTO `PersonMetric` VALUES ('25', '2', '2011-11-04 00:00:00', '70.6', '9.8', '6', '7', '5', null);
INSERT INTO `PersonMetric` VALUES ('26', '2', '2011-11-06 00:00:00', '69.5', '9.2', '7', '9', '7', null);
INSERT INTO `PersonMetric` VALUES ('27', '2', '2011-11-07 00:00:00', '69.7', '9.7', '7', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('28', '2', '2011-11-08 00:00:00', '69.2', '8.5', '8', '7.5', '8', null);
INSERT INTO `PersonMetric` VALUES ('29', '2', '2011-11-09 00:00:00', '69', '10.3', '8', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('30', '2', '2011-11-12 00:00:00', '70.6', '9.6', '8', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('31', '2', '2011-11-16 00:00:00', '70.6', '9.6', '8', '8', '6', null);
INSERT INTO `PersonMetric` VALUES ('32', '2', '2011-11-18 00:00:00', '69.8', '9.2', null, '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('33', '2', '2011-11-10 00:00:00', '69.3', '10.3', '8', '7', '6', null);
INSERT INTO `PersonMetric` VALUES ('34', '2', '2011-11-11 00:00:00', '70.3', '11.3', '8', '7', '7', null);
INSERT INTO `PersonMetric` VALUES ('35', '2', '2011-11-13 00:00:00', '70.2', '9.6', '7', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('36', '2', '2011-11-15 00:00:00', '70.9', '9.7', '8', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('37', '2', '2011-11-14 00:00:00', '70.9', '9.7', '8', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('38', '2', '2011-11-19 00:00:00', '70.6', '9.6', '7', '7.5', '6', null);
INSERT INTO `PersonMetric` VALUES ('39', '2', '2011-11-21 00:00:00', '71.5', '10.1', '6', '7', '8', null);
INSERT INTO `PersonMetric` VALUES ('40', '2', '2011-11-22 00:00:00', '70.5', '9.6', '4', '6', '5', null);
INSERT INTO `PersonMetric` VALUES ('41', '2', '2011-11-23 00:00:00', '70', '11.2', '7', '7', '8', null);
INSERT INTO `PersonMetric` VALUES ('42', '2', '2011-11-27 00:00:00', '70.8', '9.6', '7', '6', '6', null);
INSERT INTO `PersonMetric` VALUES ('43', '2', '2011-11-28 00:00:00', '70.5', '9.2', '6', '8', '6', null);
INSERT INTO `PersonMetric` VALUES ('44', '2', '2011-11-29 00:00:00', '70.5', '11.3', '8', '7', '7', null);
INSERT INTO `PersonMetric` VALUES ('45', '2', '2011-11-30 00:00:00', '70.8', '9.8', '8', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('46', '2', '2011-12-01 00:00:00', '70.6', '10.3', '8', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('47', '2', '2011-12-02 00:00:00', '70.6', '10.3', '8', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('48', '2', '2011-12-05 00:00:00', '71.6', '10.4', '8', '7', '6', null);
INSERT INTO `PersonMetric` VALUES ('49', '2', '2011-12-06 00:00:00', '70.4', '9.5', '8', '8', '6', null);
INSERT INTO `PersonMetric` VALUES ('50', '2', '2011-12-07 00:00:00', '70.2', '9.7', '6', '9', '8', null);
INSERT INTO `PersonMetric` VALUES ('51', '2', '2011-12-09 00:00:00', '71.4', '10.2', '8', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('52', '2', '2011-12-12 00:00:00', '71.1', '10.1', '8', null, '7', null);
INSERT INTO `PersonMetric` VALUES ('53', '2', '2011-12-13 00:00:00', '69.9', '9.5', '7', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('54', '2', '2011-12-14 00:00:00', '69.9', '9.5', '8', '9', '8', null);
INSERT INTO `PersonMetric` VALUES ('55', '2', '2011-12-16 00:00:00', '69.4', '9.4', '7', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('56', '2', '2011-12-13 00:00:00', '69.4', '9.4', '7', '9', '8', null);
INSERT INTO `PersonMetric` VALUES ('57', '2', '2011-12-20 00:00:00', '70.4', '9.3', '8', '7', '10', null);
INSERT INTO `PersonMetric` VALUES ('58', '2', '2012-02-08 00:00:00', '70.6', '9.9', '7', '7', '8', null);
INSERT INTO `PersonMetric` VALUES ('59', '2', '2012-01-04 00:00:00', '71.8', '12.1', '8', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('60', '2', '2012-01-05 00:00:00', '71.1', '11.1', '6', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('61', '2', '2012-01-06 00:00:00', '70.4', '10', '8', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('62', '2', '2012-01-08 00:00:00', '70.6', '10.2', '8', '10', '6', null);
INSERT INTO `PersonMetric` VALUES ('63', '2', '2012-01-10 00:00:00', '70.3', '9.5', '5', '8', '6', null);
INSERT INTO `PersonMetric` VALUES ('64', '2', '2012-01-13 00:00:00', '69.2', '9.1', '8', '7', '7', null);
INSERT INTO `PersonMetric` VALUES ('65', '2', '2012-01-17 00:00:00', '69.6', '9.1', '8', '8', '7', null);
INSERT INTO `PersonMetric` VALUES ('66', '2', '2012-05-20 00:00:00', '72.5', '20', '8', '8', null, null);
INSERT INTO `PersonMetric` VALUES ('67', '2', '2012-05-21 00:00:00', '71.2', '19.2', '8', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('68', '2', '2012-03-20 00:00:00', '69.3', '8.8', '8', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('69', '2', '2012-03-23 00:00:00', '70.3', '9.5', '8', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('70', '2', '2012-01-18 00:00:00', '70.5', '9.6', '8', '9', '8', null);
INSERT INTO `PersonMetric` VALUES ('71', '2', '2012-01-23 00:00:00', '71.4', '9.6', '7', '8', '9', null);
INSERT INTO `PersonMetric` VALUES ('72', '2', '2012-01-24 00:00:00', '70.4', '9.2', '8', '8', '8', null);
INSERT INTO `PersonMetric` VALUES ('73', '2', '2012-01-25 00:00:00', '70.3', '10', '8', '8', '10', null);
INSERT INTO `PersonMetric` VALUES ('74', '2', '2012-01-27 00:00:00', '70.2', '10', '8', '9', '7', null);

[julienschmidt]

Thanks! I'm working on it

[julienschmidt]

I have no clue why, but it seems to work for me with the current version. I tested both on Windows and a Linux VM.
Here is my test code:

package main

import (
    "database/sql"
    "fmt"
    _ "github.com/Go-SQL-Driver/MySQL"
    //_ "./MySQL"
)

type PersonMetric struct {
    Id                int
    PersonId          int
    ActualDateTime    string //time.Time
    Weight            sql.NullFloat64
    BodyFatPercentage sql.NullFloat64
    SleepQuality      sql.NullFloat64
    SleepDuration     sql.NullFloat64
    OverallFeeling    sql.NullFloat64
    Comment           sql.NullString
}

var db *sql.DB

func Setup() (err error) {
    db, err = sql.Open("mysql", "top:secret@/?charset=utf8")
    if err != nil {
        return
    }

    _, err = db.Exec("CREATE DATABASE IF NOT EXISTS `gotest`")
    if err != nil {
        return
    }

    _, err = db.Exec("USE gotest")
    if err != nil {
        return
    }

    _, err = db.Exec("DROP TABLE IF EXISTS `PersonMetric`")
    if err != nil {
        return
    }

    query := "CREATE TABLE `PersonMetric` (" +
        "`Id` int(11) NOT NULL AUTO_INCREMENT," +
        "`PersonId` int(11) DEFAULT NULL," +
        "`ActualDateTime` datetime DEFAULT NULL," +
        "`Weight` float DEFAULT NULL," +
        "`BodyFatPercentage` float DEFAULT NULL," +
        "`SleepQuality` float DEFAULT NULL," +
        "`SleepDuration` float DEFAULT NULL," +
        "`OverallFeeling` float DEFAULT NULL," +
        "`Comment` text," +
        "PRIMARY KEY (`Id`)" +
        ") ENGINE=InnoDB AUTO_INCREMENT=116 DEFAULT CHARSET=latin1;"
    _, err = db.Exec(query)
    if err != nil {
        return
    }

    query = "INSERT INTO `PersonMetric` (`Id`, `PersonId`, `ActualDateTime`, `Weight`, `BodyFatPercentage`, `SleepQuality`, `SleepDuration`, `OverallFeeling`, `Comment`) VALUES" +
        "(1, 2, '2011-10-22 00:00:00', 69.3, 10.3, 6, 9, 7, NULL)," +
        "(2, 2, '2011-10-23 00:00:00', 70.1, 9.6, 8, 9, 8, NULL)," +
        "(3, 2, '2011-10-24 00:00:00', 69.9, 9.5, 6, 8, 9, NULL)," +
        "(4, 2, '2011-11-05 00:00:00', 70.4, 9.6, 8, 8, 7, NULL)," +
        "(5, 2, '2011-11-17 00:00:00', 69.6, 9.1, 8, 7.5, 8, NULL)," +
        "(6, 2, '2011-11-25 00:00:00', 70.6, 9.6, 8, 7, 5, NULL)," +
        "(7, 2, '2011-12-21 00:00:00', 70.4, 9.4, 6, 6, 10, NULL)," +
        "(8, 2, '2012-01-03 00:00:00', 71.6, 10.1, 6, 8, 7, NULL)," +
        "(9, 2, '2012-01-11 00:00:00', 70.1, 9.6, 7, 8, 5, NULL)," +
        "(10, 2, '2012-01-12 00:00:00', 69.7, 9.4, 5, 7, 5, NULL)," +
        "(11, 2, '2012-01-26 00:00:00', 69.9, 9.8, 8, 8, 6, NULL)," +
        "(12, 2, '2011-10-25 00:00:00', 70.5, 11.5, 6, 7.5, 6, NULL)," +
        "(13, 2, '2011-10-26 00:00:00', 70.1, 9.5, 7, 8, 7, NULL)," +
        "(14, 2, '2011-10-27 00:00:00', 69.5, 9.5, 8, 8, 7, NULL)," +
        "(15, 2, '2011-10-28 00:00:00', 69.3, 9.5, 8, 9, 8, NULL)," +
        "(16, 2, '2011-10-29 00:00:00', 70.5, 11.5, 7, 9, 6, NULL)," +
        "(17, 2, '2011-10-30 00:00:00', 69.8, 9.9, 7, 9, 7, NULL)," +
        "(18, 2, '2011-07-20 00:00:00', 74.3, 11, 7, 8, 7, NULL)," +
        "(19, 2, '2011-11-01 00:00:00', 69.5, 9.5, 8, 9, 7, NULL)," +
        "(20, 2, '2011-09-30 00:00:00', 69.3, NULL, 5, 9, 7, NULL)," +
        "(21, 2, '2011-09-29 00:00:00', 69.7, NULL, 5, 8, 7, NULL)," +
        "(22, 2, '2011-09-15 00:00:00', 69.8, NULL, 7, 7.5, 7, NULL)," +
        "(23, 2, '2011-11-02 00:00:00', 70.5, 9.5, 8, 8, 6, NULL)," +
        "(24, 2, '2011-11-03 00:00:00', 69.6, 9.6, 6, 7, 6, NULL)," +
        "(25, 2, '2011-11-04 00:00:00', 70.6, 9.8, 6, 7, 5, NULL)," +
        "(26, 2, '2011-11-06 00:00:00', 69.5, 9.2, 7, 9, 7, NULL)," +
        "(27, 2, '2011-11-07 00:00:00', 69.7, 9.7, 7, 8, 7, NULL)," +
        "(28, 2, '2011-11-08 00:00:00', 69.2, 8.5, 8, 7.5, 8, NULL)," +
        "(29, 2, '2011-11-09 00:00:00', 69, 10.3, 8, 8, 7, NULL)," +
        "(30, 2, '2011-11-12 00:00:00', 70.6, 9.6, 8, 8, 7, NULL)," +
        "(31, 2, '2011-11-16 00:00:00', 70.6, 9.6, 8, 8, 6, NULL)," +
        "(32, 2, '2011-11-18 00:00:00', 69.8, 9.2, NULL, 8, 7, NULL)," +
        "(33, 2, '2011-11-10 00:00:00', 69.3, 10.3, 8, 7, 6, NULL)," +
        "(34, 2, '2011-11-11 00:00:00', 70.3, 11.3, 8, 7, 7, NULL)," +
        "(35, 2, '2011-11-13 00:00:00', 70.2, 9.6, 7, 8, 7, NULL)," +
        "(36, 2, '2011-11-15 00:00:00', 70.9, 9.7, 8, 8, 7, NULL)," +
        "(37, 2, '2011-11-14 00:00:00', 70.9, 9.7, 8, 8, 7, NULL)," +
        "(38, 2, '2011-11-19 00:00:00', 70.6, 9.6, 7, 7.5, 6, NULL)," +
        "(39, 2, '2011-11-21 00:00:00', 71.5, 10.1, 6, 7, 8, NULL)," +
        "(40, 2, '2011-11-22 00:00:00', 70.5, 9.6, 4, 6, 5, NULL)," +
        "(41, 2, '2011-11-23 00:00:00', 70, 11.2, 7, 7, 8, NULL)," +
        "(42, 2, '2011-11-27 00:00:00', 70.8, 9.6, 7, 6, 6, NULL)," +
        "(43, 2, '2011-11-28 00:00:00', 70.5, 9.2, 6, 8, 6, NULL)," +
        "(44, 2, '2011-11-29 00:00:00', 70.5, 11.3, 8, 7, 7, NULL)," +
        "(45, 2, '2011-11-30 00:00:00', 70.8, 9.8, 8, 8, 8, NULL)," +
        "(46, 2, '2011-12-01 00:00:00', 70.6, 10.3, 8, 8, 7, NULL)," +
        "(47, 2, '2011-12-02 00:00:00', 70.6, 10.3, 8, 8, 7, NULL)," +
        "(48, 2, '2011-12-05 00:00:00', 71.6, 10.4, 8, 7, 6, NULL)," +
        "(49, 2, '2011-12-06 00:00:00', 70.4, 9.5, 8, 8, 6, NULL)," +
        "(50, 2, '2011-12-07 00:00:00', 70.2, 9.7, 6, 9, 8, NULL)," +
        "(51, 2, '2011-12-09 00:00:00', 71.4, 10.2, 8, 8, 8, NULL)," +
        "(52, 2, '2011-12-12 00:00:00', 71.1, 10.1, 8, NULL, 7, NULL)," +
        "(53, 2, '2011-12-13 00:00:00', 69.9, 9.5, 7, 8, 7, NULL)," +
        "(54, 2, '2011-12-14 00:00:00', 69.9, 9.5, 8, 9, 8, NULL)," +
        "(55, 2, '2011-12-16 00:00:00', 69.4, 9.4, 7, 8, 8, NULL)," +
        "(56, 2, '2011-12-13 00:00:00', 69.4, 9.4, 7, 9, 8, NULL)," +
        "(57, 2, '2011-12-20 00:00:00', 70.4, 9.3, 8, 7, 10, NULL)," +
        "(58, 2, '2012-02-08 00:00:00', 70.6, 9.9, 7, 7, 8, NULL)," +
        "(59, 2, '2012-01-04 00:00:00', 71.8, 12.1, 8, 8, 8, NULL)," +
        "(60, 2, '2012-01-05 00:00:00', 71.1, 11.1, 6, 8, 8, NULL)," +
        "(61, 2, '2012-01-06 00:00:00', 70.4, 10, 8, 8, 8, NULL)," +
        "(62, 2, '2012-01-08 00:00:00', 70.6, 10.2, 8, 10, 6, NULL)," +
        "(63, 2, '2012-01-10 00:00:00', 70.3, 9.5, 5, 8, 6, NULL)," +
        "(64, 2, '2012-01-13 00:00:00', 69.2, 9.1, 8, 7, 7, NULL)," +
        "(65, 2, '2012-01-17 00:00:00', 69.6, 9.1, 8, 8, 7, NULL)," +
        "(66, 2, '2012-05-20 00:00:00', 72.5, 20, 8, 8, NULL, NULL)," +
        "(67, 2, '2012-05-21 00:00:00', 71.2, 19.2, 8, 8, 8, NULL)," +
        "(68, 2, '2012-03-20 00:00:00', 69.3, 8.8, 8, 8, 8, NULL)," +
        "(69, 2, '2012-03-23 00:00:00', 70.3, 9.5, 8, 8, 8, NULL)," +
        "(70, 2, '2012-01-18 00:00:00', 70.5, 9.6, 8, 9, 8, NULL)," +
        "(71, 2, '2012-01-23 00:00:00', 71.4, 9.6, 7, 8, 9, NULL)," +
        "(72, 2, '2012-01-24 00:00:00', 70.4, 9.2, 8, 8, 8, NULL)," +
        "(73, 2, '2012-01-25 00:00:00', 70.3, 10, 8, 8, 10, NULL)," +
        "(74, 2, '2012-01-27 00:00:00', 70.2, 10, 8, 9, 7, NULL);"
    res, err := db.Exec(query)
    if err != nil {
        return
    }

    rowsAffected, err := res.RowsAffected()
    if err != nil {
        return
    }
    lastInsertId, err := res.LastInsertId()
    if err != nil {
        return
    }
    fmt.Println("RowsAffected: ", rowsAffected, " LastInserID: ", lastInsertId)

    return
}

func GetByPersonId(personId int) (*[]PersonMetric, error) {
    rows, err := db.Query("SELECT Id, PersonId, ActualDateTime, Weight, BodyFatPercentage, SleepQuality, SleepDuration, OverallFeeling, Comment FROM PersonMetric WHERE PersonId=?;", personId)
    var list []PersonMetric
    if err == nil {
        for rows.Next() {
            var personMetric PersonMetric
            err := rows.Scan(&personMetric.Id, &personMetric.PersonId, &personMetric.ActualDateTime, &personMetric.Weight, &personMetric.BodyFatPercentage, &personMetric.SleepQuality, &personMetric.SleepDuration, &personMetric.OverallFeeling, &personMetric.Comment)
            if err != nil {
                return nil, err
            }
            list = append(list, personMetric)
        }
    }
    return &list, err
}

func main() {
    err := Setup()
    if err != nil {
        panic(err)
    }

    list, err := GetByPersonId(2)
    if err != nil {
        panic(err)
    }
    for i, personMetric := range *list {
        fmt.Print(i, `:   `, personMetric.Id, ` | `, personMetric.ActualDateTime, ` | `)

        if personMetric.Weight.Valid {
            fmt.Print(personMetric.Weight.Float64)
        } else {
            fmt.Print(nil)
        }

        fmt.Print(` | `)

        if personMetric.BodyFatPercentage.Valid {
            fmt.Print(personMetric.BodyFatPercentage.Float64)
        } else {
            fmt.Print(nil)
        }

        fmt.Print(` | `)

        if personMetric.SleepQuality.Valid {
            fmt.Print(personMetric.SleepQuality.Float64)
        } else {
            fmt.Print(nil)
        }

        fmt.Print(` | `)

        if personMetric.SleepDuration.Valid {
            fmt.Print(personMetric.SleepDuration.Float64)
        } else {
            fmt.Print(nil)
        }

        fmt.Print(` | `)

        if personMetric.OverallFeeling.Valid {
            fmt.Print(personMetric.OverallFeeling.Float64)
        } else {
            fmt.Print(nil)
        }

        fmt.Print(` | `)

        if personMetric.Comment.Valid {
            fmt.Print(personMetric.Comment.String)
        } else {
            fmt.Print(nil)
        }

        fmt.Println()
    }
}

Output:

RowsAffected:  74  LastInserID:  74
0:   1 | 2011-10-22 00:00:00 | 69.3 | 10.3 | 6 | 9 | 7 | <nil>
1:   2 | 2011-10-23 00:00:00 | 70.1 | 9.6 | 8 | 9 | 8 | <nil>
2:   3 | 2011-10-24 00:00:00 | 69.9 | 9.5 | 6 | 8 | 9 | <nil>
3:   4 | 2011-11-05 00:00:00 | 70.4 | 9.6 | 8 | 8 | 7 | <nil>
4:   5 | 2011-11-17 00:00:00 | 69.6 | 9.1 | 8 | 7.5 | 8 | <nil>
5:   6 | 2011-11-25 00:00:00 | 70.6 | 9.6 | 8 | 7 | 5 | <nil>
6:   7 | 2011-12-21 00:00:00 | 70.4 | 9.4 | 6 | 6 | 10 | <nil>
7:   8 | 2012-01-03 00:00:00 | 71.6 | 10.1 | 6 | 8 | 7 | <nil>
8:   9 | 2012-01-11 00:00:00 | 70.1 | 9.6 | 7 | 8 | 5 | <nil>
9:   10 | 2012-01-12 00:00:00 | 69.7 | 9.4 | 5 | 7 | 5 | <nil>
10:   11 | 2012-01-26 00:00:00 | 69.9 | 9.8 | 8 | 8 | 6 | <nil>
11:   12 | 2011-10-25 00:00:00 | 70.5 | 11.5 | 6 | 7.5 | 6 | <nil>
12:   13 | 2011-10-26 00:00:00 | 70.1 | 9.5 | 7 | 8 | 7 | <nil>
13:   14 | 2011-10-27 00:00:00 | 69.5 | 9.5 | 8 | 8 | 7 | <nil>
14:   15 | 2011-10-28 00:00:00 | 69.3 | 9.5 | 8 | 9 | 8 | <nil>
15:   16 | 2011-10-29 00:00:00 | 70.5 | 11.5 | 7 | 9 | 6 | <nil>
16:   17 | 2011-10-30 00:00:00 | 69.8 | 9.9 | 7 | 9 | 7 | <nil>
17:   18 | 2011-07-20 00:00:00 | 74.3 | 11 | 7 | 8 | 7 | <nil>
18:   19 | 2011-11-01 00:00:00 | 69.5 | 9.5 | 8 | 9 | 7 | <nil>
19:   20 | 2011-09-30 00:00:00 | 69.3 | <nil> | 5 | 9 | 7 | <nil>
20:   21 | 2011-09-29 00:00:00 | 69.7 | <nil> | 5 | 8 | 7 | <nil>
21:   22 | 2011-09-15 00:00:00 | 69.8 | <nil> | 7 | 7.5 | 7 | <nil>
22:   23 | 2011-11-02 00:00:00 | 70.5 | 9.5 | 8 | 8 | 6 | <nil>
23:   24 | 2011-11-03 00:00:00 | 69.6 | 9.6 | 6 | 7 | 6 | <nil>
24:   25 | 2011-11-04 00:00:00 | 70.6 | 9.8 | 6 | 7 | 5 | <nil>
25:   26 | 2011-11-06 00:00:00 | 69.5 | 9.2 | 7 | 9 | 7 | <nil>
26:   27 | 2011-11-07 00:00:00 | 69.7 | 9.7 | 7 | 8 | 7 | <nil>
27:   28 | 2011-11-08 00:00:00 | 69.2 | 8.5 | 8 | 7.5 | 8 | <nil>
28:   29 | 2011-11-09 00:00:00 | 69 | 10.3 | 8 | 8 | 7 | <nil>
29:   30 | 2011-11-12 00:00:00 | 70.6 | 9.6 | 8 | 8 | 7 | <nil>
30:   31 | 2011-11-16 00:00:00 | 70.6 | 9.6 | 8 | 8 | 6 | <nil>
31:   32 | 2011-11-18 00:00:00 | 69.8 | 9.2 | <nil> | 8 | 7 | <nil>
32:   33 | 2011-11-10 00:00:00 | 69.3 | 10.3 | 8 | 7 | 6 | <nil>
33:   34 | 2011-11-11 00:00:00 | 70.3 | 11.3 | 8 | 7 | 7 | <nil>
34:   35 | 2011-11-13 00:00:00 | 70.2 | 9.6 | 7 | 8 | 7 | <nil>
35:   36 | 2011-11-15 00:00:00 | 70.9 | 9.7 | 8 | 8 | 7 | <nil>
36:   37 | 2011-11-14 00:00:00 | 70.9 | 9.7 | 8 | 8 | 7 | <nil>
37:   38 | 2011-11-19 00:00:00 | 70.6 | 9.6 | 7 | 7.5 | 6 | <nil>
38:   39 | 2011-11-21 00:00:00 | 71.5 | 10.1 | 6 | 7 | 8 | <nil>
39:   40 | 2011-11-22 00:00:00 | 70.5 | 9.6 | 4 | 6 | 5 | <nil>
40:   41 | 2011-11-23 00:00:00 | 70 | 11.2 | 7 | 7 | 8 | <nil>
41:   42 | 2011-11-27 00:00:00 | 70.8 | 9.6 | 7 | 6 | 6 | <nil>
42:   43 | 2011-11-28 00:00:00 | 70.5 | 9.2 | 6 | 8 | 6 | <nil>
43:   44 | 2011-11-29 00:00:00 | 70.5 | 11.3 | 8 | 7 | 7 | <nil>
44:   45 | 2011-11-30 00:00:00 | 70.8 | 9.8 | 8 | 8 | 8 | <nil>
45:   46 | 2011-12-01 00:00:00 | 70.6 | 10.3 | 8 | 8 | 7 | <nil>
46:   47 | 2011-12-02 00:00:00 | 70.6 | 10.3 | 8 | 8 | 7 | <nil>
47:   48 | 2011-12-05 00:00:00 | 71.6 | 10.4 | 8 | 7 | 6 | <nil>
48:   49 | 2011-12-06 00:00:00 | 70.4 | 9.5 | 8 | 8 | 6 | <nil>
49:   50 | 2011-12-07 00:00:00 | 70.2 | 9.7 | 6 | 9 | 8 | <nil>
50:   51 | 2011-12-09 00:00:00 | 71.4 | 10.2 | 8 | 8 | 8 | <nil>
51:   52 | 2011-12-12 00:00:00 | 71.1 | 10.1 | 8 | <nil> | 7 | <nil>
52:   53 | 2011-12-13 00:00:00 | 69.9 | 9.5 | 7 | 8 | 7 | <nil>
53:   54 | 2011-12-14 00:00:00 | 69.9 | 9.5 | 8 | 9 | 8 | <nil>
54:   55 | 2011-12-16 00:00:00 | 69.4 | 9.4 | 7 | 8 | 8 | <nil>
55:   56 | 2011-12-13 00:00:00 | 69.4 | 9.4 | 7 | 9 | 8 | <nil>
56:   57 | 2011-12-20 00:00:00 | 70.4 | 9.3 | 8 | 7 | 10 | <nil>
57:   58 | 2012-02-08 00:00:00 | 70.6 | 9.9 | 7 | 7 | 8 | <nil>
58:   59 | 2012-01-04 00:00:00 | 71.8 | 12.1 | 8 | 8 | 8 | <nil>
59:   60 | 2012-01-05 00:00:00 | 71.1 | 11.1 | 6 | 8 | 8 | <nil>
60:   61 | 2012-01-06 00:00:00 | 70.4 | 10 | 8 | 8 | 8 | <nil>
61:   62 | 2012-01-08 00:00:00 | 70.6 | 10.2 | 8 | 10 | 6 | <nil>
62:   63 | 2012-01-10 00:00:00 | 70.3 | 9.5 | 5 | 8 | 6 | <nil>
63:   64 | 2012-01-13 00:00:00 | 69.2 | 9.1 | 8 | 7 | 7 | <nil>
64:   65 | 2012-01-17 00:00:00 | 69.6 | 9.1 | 8 | 8 | 7 | <nil>
65:   66 | 2012-05-20 00:00:00 | 72.5 | 20 | 8 | 8 | <nil> | <nil>
66:   67 | 2012-05-21 00:00:00 | 71.2 | 19.2 | 8 | 8 | 8 | <nil>
67:   68 | 2012-03-20 00:00:00 | 69.3 | 8.8 | 8 | 8 | 8 | <nil>
68:   69 | 2012-03-23 00:00:00 | 70.3 | 9.5 | 8 | 8 | 8 | <nil>
69:   70 | 2012-01-18 00:00:00 | 70.5 | 9.6 | 8 | 9 | 8 | <nil>
70:   71 | 2012-01-23 00:00:00 | 71.4 | 9.6 | 7 | 8 | 9 | <nil>
71:   72 | 2012-01-24 00:00:00 | 70.4 | 9.2 | 8 | 8 | 8 | <nil>
72:   73 | 2012-01-25 00:00:00 | 70.3 | 10 | 8 | 8 | 10 | <nil>
73:   74 | 2012-01-27 00:00:00 | 70.2 | 10 | 8 | 9 | 7 | <nil>

Can you confirm, that it works now? Or did I miss something? 😮

Don't forget to update with go get -u github.com/Go-SQL-Driver/MySQL 😉