建立测试数据表

CREATE TABLE `user` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(25) NOT NULL DEFAULT '',
  `age` int(11) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=7 DEFAULT CHARSET=utf8

上代码

package main

import (
    // sql.DB 是接口协议，具体的DB操作是通过driver执行
    // 但是不能通过driver直接操作，需要通过接口操作，此处匿名引入，自动注册初始化到sql.DB中
    _ "github.com/go-sql-driver/mysql"
    "database/sql"
    "fmt"
)

/**
 * DB 连接池
 */
type DBWorker struct {
    Dsn string
    Db *sql.DB
}

// 对应数据表字段
type userTB struct {
    Id int
    Name sql.NullString   // 数据类型设置为 NullXXX，以便读取时判断是否赋值
    Age sql.NullInt64
}

func main()  {
    var err error
    dbw := DBWorker{
        // 格式大概为：user:password@protocol(ip:port)/database?charset=utf8
        Dsn: "root:XXXXXX(@tcp(localhost:3307)/test?charset=utf8",
    }
    dbw.Db, err = sql.Open("mysql", dbw.Dsn)
    if err != nil {
        panic(err)
        return
    }

    defer dbw.Db.Close()

    dbw.insertData()

    dbw.queryData()
}

// 插入数据测试
func (dbw* DBWorker) insertData()  {
    stmt, _ := dbw.Db.Prepare(`INSERT INTO user (name, age) VALUES (?, ?)`)

    defer stmt.Close()

    ret, err := stmt.Exec("虚无缥缈", 23)

    if err != nil {
        fmt.Printf("insert data error:%v\n", err)
        return
    }

    if LastInsertId, err := ret.LastInsertId(); err == nil {
        fmt.Printf("LastInsertId %d\n", LastInsertId)
    }

    if RowsAffected, err := ret.RowsAffected(); err == nil {
        fmt.Printf("RowsAffected %d\n", RowsAffected)
    }
}

// 查询数据测试
func (dbw *DBWorker) queryData()  {
    stmt, _ := dbw.Db.Prepare("SELECT * FROM user WHERE age >= ? and age < ?")

    defer stmt.Close()

    user := userTB{}

    rows, err := stmt.Query(20, 30)

    defer rows.Close()

    if err != nil {
        fmt.Printf("query data error : %v\n", err)
        return;
    }

    for rows.Next()  {
        // SCAN赋值的顺序需要与拉取出来的数据一一对应
        // 建表时是 id,name,age,此处赋值相对应的为Id, Name, Age
        err = rows.Scan(&user.Id, &user.Name, &user.Age)

        if err != nil {
            fmt.Printf("scan error : %v\n", err)
            continue
        }

        // 运行为空的情形下，给赋值默认值
        if !user.Name.Valid {
            user.Name.String = ""
        }

        // 运行为空的情形下，给赋值默认值
        if !user.Age.Valid {
            user.Age.Int64 = 0
        }

        fmt.Println("id: ", user.Id, " name: ", user.Name.String, " age: ", int(user.Age.Int64))
    }

    err = rows.Err()
    if err != nil {
        fmt.Printf("rows.Err: %v", err)
    }
}

运行结果

LastInsertId 7
RowsAffected 1
id:  1  name:  a  age:  25
id:  5  name:  石义波  age:  23
id:  6  name:  石义波  age:  23
id:  7  name:  虚无缥缈  age:  23

Process finished with exit code 0