Run 2 query in golang , commit and rollback

var db, err = sql.Open("mssql", connString)
	if err != nil {
		log.Println("Open connection failed:", err)
	}
	err = db.Ping()
	if err != nil {
		log.Println("Cannot connect: ", err)
	}
	defer db.Close()

	if err != nil {
		fmt.Println(err.Error())
		return "Failed to Connect to Database", err
	}
	tx, err := db.Begin()
	var query string
	query = `	`
   
_, err = db.Exec(query)
	if err != nil {
		return err.Error(), nil
	}

for _, statusHistory := range data.StatusHistory {
		var querydetail = ``
}
	_, err = db.Exec(querydetail)
		if err != nil {
			return err.Error(), nil
		}
	}
	if err != nil {
		tx.Rollback()
		return err.Error(), nil
	} else {
		tx.Commit()
		return "success to  Insert Data : ", nil
	}

}