Express项目中操作MySQL的步骤

node -v
mysql --version

npm install mysql2

// 引入mysql2模块
const mysql = require('mysql2');
// 创建连接池
const pool = mysql.createPool({
    host: 'localhost',       // 数据库主机名
    user: 'root',            // 数据库用户名
    password: 'your_password', // 数据库密码
    database: 'your_database' // 数据库名
});
// 导出连接池
module.exports = pool;

const express = require('express');
const app = express();
const pool = require('./config/db-config'); // 引入数据库连接池
// 查询示例
app.get('/users', (req, res) => {
    const sql = 'SELECT * FROM users';
    pool.query(sql, (error, results) => {
        if (error) throw error;
        res.json(results);
    });
});
// 插入示例
app.post('/users', (req, res) => {
    const user = req.body;
    const sql = 'INSERT INTO users (username, password) VALUES (?, ?)';
    pool.query(sql, [user.username, user.password], (error, results) => {
        if (error) throw error;
        res.json({ message: 'User created successfully', id: results.insertId });
    });
});
// 删除示例
app.delete('/users/:id', (req, res) => {
    const id = req.params.id;
    const sql = 'DELETE FROM users WHERE id = ?';
    pool.query(sql, [id], (error, results) => {
        if (error) throw error;
        res.json({ message: 'User deleted successfully', affectedRows: results.affectedRows });
    });
});
// 启动服务器
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
    console.log(`Server is running on port ${PORT}`);
});

pool.query('SELECT * FROM users', (error, results) => {
    if (error) throw error;
    results.forEach(user => {
        console.log(`User: ${user.username}`);
    });
});

pool.query('INSERT INTO users (username, password) VALUES (?, ?)', [username, password], (error, results) => {
    if (error) throw error;
    if (results.affectedRows === 1) {
        console.log('User created successfully');
    } else {
        console.log('Failed to create user');
    }
});