带有express和mysql的Node.js应用程序接口-获取记录计数、页码...并提供分页

npm install express mysql

const express = require('express');
const mysql = require('mysql');

const app = express();

// 创建MySQL连接
const connection = mysql.createConnection({
  host: 'localhost',
  user: 'root',
  password: 'password',
  database: 'database_name'
});

// 连接到MySQL数据库
connection.connect((err) => {
  if (err) {
    console.error('Error connecting to MySQL database: ' + err.stack);
    return;
  }
  console.log('Connected to MySQL database');
});

// 定义API路由
app.get('/api/records', (req, res) => {
  const page = req.query.page || 1;
  const pageSize = req.query.pageSize || 10;

  // 查询记录总数
  connection.query('SELECT COUNT(*) AS total FROM records', (err, results) => {
    if (err) {
      console.error('Error querying records count: ' + err.stack);
      res.status(500).json({ error: 'Internal server error' });
      return;
    }

    const total = results[0].total;

    // 查询分页数据
    connection.query('SELECT * FROM records LIMIT ?, ?', [(page - 1) * pageSize, pageSize], (err, results) => {
      if (err) {
        console.error('Error querying records: ' + err.stack);
        res.status(500).json({ error: 'Internal server error' });
        return;
      }

      res.json({
        total,
        page,
        pageSize,
        data: results
      });
    });
  });
});

// 启动服务器
app.listen(3000, () => {
  console.log('Server is running on port 3000');
});

node app.js