golang sqlx捕捉错误

go get github.com/jmoiron/sqlx

package main
 
import (
	"database/sql"
	_"github.com/go-sql-driver/mysql"
	"github.com/jmoiron/sqlx"
	"log"
	"fmt"
)
 
type Student struct {
	Id         int    `db:"id"`
	Name       string `db:"name"`
	Nick       string `db:"nick"`
	Country    string `db:"country"`
	Province   string `db:"province"`
	City       string `db:"city"`
	ImgUrl     string `db:"img_url"`
	Status     int    `db:"status"`
	CreateTime string `db:"create_time"`
}
 
func main()  {
	dns := fmt.Sprintf("%s:%s@tcp(%s)/%s?charset=utf8", dbuser, dbpwd, dbhost, dbname)
	db, err := sqlx.Connect("mysql", dns)
	if err != nil {
        log.Fatalln(err)
	}
	defer db.Close()
 
	tx := db.MustBegin()
	tx.MustExec(`INSERT INTO student VALUES ('1', 'Jack', 'Jack', 'England', '', '', 'http://img2.imgtn.bdimg.com/it/u=3588772980,2454248748&fm=27&gp=0.jpg', '1', '2018-06-26 17:08:35');`)
	tx.MustExec(`INSERT INTO student VALUES ('2', 'Emily', 'Emily', 'England', '', '', 'http://img2.imgtn.bdimg.com/it/u=3588772980,2454248748&fm=27&gp=0.jpg', '2', null);`)
	err = tx.Commit()
	if err != nil {
		log.Fatalln(err)
	}
 
}