当我键入的用户名是有在表“用户”我没有面临任何错误，但当我键入错误的名称，这是用户名是没有在表中我面临的错误，这是错误和代码如下所附.

export const register = (req, res) => {
  //CHECK USER IF EXISTS

  const q = "SELECT * FROM users WHERE username = ?";

  const result = db.query(q, [req.body.username]);

  db.query(q, [req.body.username], (err, result, data) => {
    if (err) return res.status(500).json(err);
    if (data.length) return res.status(409).json("User already exists!");

    //CREATE A NEW USER
    //Hash the password
    const salt = bcrypt.genSaltSync(10);
    const hashedPassword = bcrypt.hashSync(req.body.password, salt);

    const q =
      "INSERT INTO users (`username`,`email`,`password`,`name`) VALUE (?)";

    const values = [
      req.body.username,
      req.body.email,
      hashedPassword,
      req.body.name,
    ];

    db.query(q, [values], (err, data ) => {
      if (err) return res.status(500).json(err);
      return res.status(200).json("User has been created.");
    });
  });
};