我的输入密码和数据库密码是一样的，那么函数也返回false。这里的比较方法工作不正常。每次提供正确的密码时，我都会得到false作为回报。

app.post('/login', (req, res) => {

              const username = req.body.username;
              const password = req.body.password;

          db.query('SELECT * FROM dataa WHERE username = ?',[username], function (error, rows, fields) {
              if (error) {
              // console.log("error ocurred",error);
              res.send({
              "code":400,
              "failed":"error ocurred"
              })
              }else{
                  // console.log('The solution is: ', results);
                  if(rows.length >0){

                    console.log(bcrypt.compareSync(password, rows[0].password));

                      if(bcrypt.compareSync(password, rows[0].password)){
                          res.send({
                          "code":200,
                          "success":"login sucessfull"
                          });
                      }
                      else{
                          res.send({
                          "code":204,
                          "success":"Email and password does not match"
                          });
                      }
                  }
                  else{
                  res.send({
                  "code":204,
                  "success":"Email does not exits"
                  });
                  }
              }
          });

})