第五单元 go操作mysql

一、标准包引用
二、实现增删改查功能

一、标准包引用

github.com/go-sql-driver/mysql （mysql驱动）
 github.com/jmoiron/sqlx （基于mysql驱动的封装）
命令行输入 ：
  go get github.com/go-sql-driver/mysql
  go get github.com/jmoiron/sqlx

二、实现增删改查功能
1.数据库连接
用法:database, err := sqlx.Open(数据库驱动, 用户名:密码@tcp(db地址:端口)/数据库名)
database, err := sqlx.Open("mysql", "root:root@tcp(127.0.0.1:3306)/test")

示例代码
// test
package main

import (
	"fmt"

	_ "github.com/go-sql-driver/mysql"
	"github.com/jmoiron/sqlx"
)

func main() {

	_, err := sqlx.Open("mysql", "root:root@tcp(127.0.0.1:3306)/1803a")
	if err != nil {
		fmt.Println("数据库连接失败", err.Error())

	} else {
		fmt.Println("数据库连接成功")

	}

}


2.新建表结构
CREATE TABLE `person` (
    `user_id` int(11) NOT NULL AUTO_INCREMENT,
    `username` varchar(260) DEFAULT NULL,
    `sex` varchar(260) DEFAULT NULL,
    `email` varchar(260) DEFAULT NULL,
    PRIMARY KEY (`user_id`)
  ) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;


3.新增功能实现

type Person struct {
    UserId   int    `db:"user_id"`
    Username string `db:"username"`
    Sex      string `db:"sex"`
    Email    string `db:"email"`
}

var Db *sqlx.DB

func init() {
    database, err := sqlx.Open("mysql", "root:root@tcp(127.0.0.1:3306)/test")
    if err != nil {
        fmt.Println("open mysql failed,", err)
        return
    }
    Db = database
    defer db.Close()  // 注意这行代码要写在上面err判断的下面
}

func main() {
    r, err := Db.Exec("insert into person(username, sex, email)values(?, ?, ?)", "stu001", "man", "stu01@qq.com")
    if err != nil {
        fmt.Println("exec failed, ", err)
        return
    }
    id, err := r.LastInsertId()
    if err != nil {
        fmt.Println("exec failed, ", err)
        return
    }

    fmt.Println("insert succ:", id)
}


4.查询实现

代码示例

package main

import (
	"fmt"

	_ "github.com/go-sql-driver/mysql"
	"github.com/jmoiron/sqlx"
)

type Person struct {
	UserId   int    `db:"user_id"`
	Username string `db:"username"`
	Sex      string `db:"sex"`
	Email    string `db:"email"`
}

var Db *sqlx.DB

func init() {
	database, err := sqlx.Open("mysql", "root:root@tcp(127.0.0.1:3306)/1803a")
	if err != nil {
		fmt.Println("open mysql failed,", err)
		return
	}
	Db = database
	//defer Db.Close() // 注意这行代码要写在上面err判断的下面
}

func main() {
	var person []Person
	err := Db.Select(&person, "select user_id, username, sex, email from person where user_id=?", 1)
	if err != nil {
		fmt.Println("exec failed, ", err)
		return
	}

	fmt.Println("select succ:", person)
}

5.更新操作

package main

import (
	"fmt"

	_ "github.com/go-sql-driver/mysql"
	"github.com/jmoiron/sqlx"
)

type Person struct {
	UserId   int    `db:"user_id"`
	Username string `db:"username"`
	Sex      string `db:"sex"`
	Email    string `db:"email"`
}

var Db *sqlx.DB

func init() {
	database, err := sqlx.Open("mysql", "root:root@tcp(127.0.0.1:3306)/1803a")
	if err != nil {
		fmt.Println("open mysql failed,", err)
		return
	}
	Db = database
	//defer Db.Close() // 注意这行代码要写在上面err判断的下面
}

func main() {
	res, err := Db.Exec("update person set username=? where user_id=?", "stu0003", 1)
	if err != nil {
		fmt.Println("exec failed, ", err)
		return
	}
	row, err := res.RowsAffected()
	if err != nil {
		fmt.Println("rows failed, ", err)
	}
	fmt.Println("update succ:", row)
}


6.删除操作
package main

import (
	"fmt"

	_ "github.com/go-sql-driver/mysql"
	"github.com/jmoiron/sqlx"
)

type Person struct {
	UserId   int    `db:"user_id"`
	Username string `db:"username"`
	Sex      string `db:"sex"`
	Email    string `db:"email"`
}

var Db *sqlx.DB

func init() {
	database, err := sqlx.Open("mysql", "root:root@tcp(127.0.0.1:3306)/1803a")
	if err != nil {
		fmt.Println("open mysql failed,", err)
		return
	}
	Db = database
	//defer Db.Close() // 注意这行代码要写在上面err判断的下面
}

func main() {
	res, err := Db.Exec("delete from person where user_id=?", 1)
	if err != nil {
		fmt.Println("exec failed, ", err)
		return
	}
	row, err := res.RowsAffected()
	if err != nil {
		fmt.Println("rows failed, ", err)
	}
	fmt.Println("delete succ:", row)
}