package main

import (
	"fmt"
	"github.com/jmoiron/sqlx"
	"log"

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

// sqlx 另外的库

var databasE *sqlx.DB

type users struct {
	ID   int
	NAME string
	AGE  int
}

func main() {
	err := initd()
	if err != nil {
		return
	}
	//查询单行，不需要scan也能拿到结果
	sqlstr := `select id,name,age from user where id=1`
	var u users
	err = databasE.Get(&u, sqlstr)
	if err != nil {
		return
	}
	fmt.Println(u)
	//查询多行
	var ulist = make([]users, 0, 1) //引用类型初始化
	sqlstr2 := `select id,name,age from user`
	//必须要传指针
	err = databasE.Select(&ulist, sqlstr2)
	if err != nil {
		fmt.Println(err)
		return
	}
	fmt.Println(ulist)
}

func initd() (err error) {
	databasE, err = sqlx.Connect("mysql", "root:123456@tcp(43.143.245.135:3306)/user")
	if err != nil {
		log.Println(err)
		return err
	}
	//connect方法提供了ping。所以不需要ping
	//err = databasE.Ping()
	//if err != nil {
	//	log.Println(err)
	//	return err
	//}
	log.Println("Successfully connected to mysql")
	databasE.SetMaxOpenConns(10)
	databasE.SetMaxIdleConns(5)
	return nil
}