javascript - 一个简单的 Nodejs MySQL 查询

Question

我正在尝试将 mysql 与 nodejs 一起使用:尝试运行查询:select count(*) from TABLE。结果出来了

[ RowDataPacket { 'count(*)': 33 } ]

我只要33作为答案，javascript框架代码如下

var express = require('express');
var router = express.Router();
var mysql = require('mysql');

var con = mysql.createConnection({
  host: "localhost",
  user: "honolulu",
  password: "honolulu",
  database: "db"
});


con.connect(function(err) {
  if (err) throw err;
  console.log("Connected to question database file 1!");
});
var but=20
con.query('select count(*) from qpsc',function (err, result) {
    if (err) throw err;
    but=result;
    console.log(but);
  });
/* GET home page. */
router.get('/', function(req, res, next) {
  res.render('index', { title: 'Express' });
});
router.get('/file', function(req, res, next) {
  res.render('index2',{ num_buttons: '20'});
  // console.log("RENDERED FROM INDEX.js");
});

module.exports = router;

那么，我该怎么办？请帮忙。

Answer 1

由于结果是:

[ RowDataPacket { 'count(*)': 33 } ]

您可以通过以下方式获得 33:

var theCount = result[0]['count(*)'];

因此，您的代码经过调整后将是:

con.query('select count(*) from qpsc',function (err, result) {
  if (err) throw err;
  but = result[0]['count(*)'];
  console.log(but);
});