package db

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

var (
    userName  string = "root"
    password  string = "jEER3Dc="
    ipAddrees string = "47.110.138.172"
    port      int    = 3306
    dbName    string = "newDB"
    charset   string = "utf8"
)

func connectMysql() *sqlx.DB {
    dsn := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?charset=%s", userName, password, ipAddrees, port, dbName, charset)
    Db, err := sqlx.Open("mysql", dsn)
    if err != nil {
        fmt.Printf("mysql connect failed, detail is [%v]", err.Error())
    }
    return Db
}

func queryData(Db *sqlx.DB) {
    rows, err := Db.Query("select user_id as userId, user_name as userName from sys_user")
    if err != nil {
        fmt.Printf("query faied, error:[%v]", err.Error())
        return
    }
    for rows.Next() {
        //定义变量接收查询数据
        var userId, userName string

        err := rows.Scan(&userId,&userName)
        if err != nil {
            fmt.Printf("get data failed, error:[%v]", err.Error())
        }
        fmt.Println(userId, userName)
    }

    //关闭结果集（释放连接）
    rows.Close()
}

func selectData(Db *sqlx.DB)  {
    type userInfo struct {
        UserId string `db:"user_id"`
        UserName string `db:"user_name"`
    }

    var userInfos []userInfo
    err := Db.Select(&userInfos, "select user_id, user_name from sys_user")
    if err!= nil {
        fmt.Printf("query fail : [%v]" , err)
        return
    }

    for _, user := range userInfos {
        fmt.Println(user.UserId,"=>", user.UserName)
    }
}