java - spring mvc删除用户出错

Question

我无法删除用户。这是我单击删除按钮时收到的错误。 org.springframework.dao.TransientDataAccessResourceException:PreparedStatementCallback； SQL [从用户删除，其中 id = '1'];参数索引超出范围(1 > 参数数量，即 0)。；嵌套异常是 java.sql.SQLException: 参数索引超出范围(1 > 参数数量，即 0)。请帮忙，非常感谢

Jdbc删除函数

public int deleteUser(int id){
        String SQL = "DELETE FROM users WHERE id = '"+id+"'";
        System.out.print(SQL);
        int user = jdbcTemplateObject.update(SQL, id);
        return user;
    }

删除 Controller

RequestMapping(value = "/delete", method = RequestMethod.GET)
    public ModelAndView delete(@ModelAttribute("SpringWeb")User user, ModelMap model, HttpServletRequest request)
    {
        try
        {
            SyntacksJdbc syntacksJdbc = (SyntacksJdbc)context.getBean("syntacksJdbc");
            System.out.println(request.getParameter("id"));
            int id = Integer.parseInt(request.getParameter("id"));
            int user1 = syntacksJdbc.deleteUser(id);
            model.addAttribute("message", "Questions updated successfully.");
        }
        catch(Exception e)
        {
            System.out.print(e);
            model.addAttribute("message", "Error occured in posting question.");
        }

        return new ModelAndView("users");

在我的 jsp 按钮上

 <a href="/Project/delete?id=${user.id}" name="delete"><button type= submit>Delete</button>

Answer 1

将查询更改为

DELETE FROM users WHERE id = ?

因为您正在尝试设置参数值