使用Node操作MySQL的两种方式

mkdir myproject
cd myproject
npm init -y
npm install --save mysql2

const mysql = require('mysql2');

const connection = mysql.createConnection({
  host: 'localhost',
  port: 3306,
  user: 'root',
  password: 'your_password',
  database: 'practice'
});

connection.query('SELECT * FROM customers', (err, results, fields) => {
  if (err) throw err;
  console.log(results);
  console.log(fields.map(item => item.name));
});

connection.execute('INSERT INTO customers (name) VALUES (?)', ['Zhang'], (err, results) => {
  if (err) throw err;
  console.log('Insert successful');
});

connection.execute('UPDATE customers SET name="Li" WHERE name="Zhang"', (err) => {
  if (err) throw err;
  console.log('Update successful');
});

connection.execute('DELETE FROM customers WHERE name="Li"', (err) => {
  if (err) throw err;
  console.log('Delete successful');
});

const mysql = require('mysql2/promise');

(async () => {
  const pool = mysql.createPool({
    host: 'localhost',
    user: 'root',
    password: 'your_password',
    database: 'practice',
    waitForConnections: true, // 如果没有可用连接，等待而不是立即抛出错误
    connectionLimit: 10, // 连接池中最大连接数
    queueLimit: 0 // 最大排队数量，0表示不限制
  });

  const [results] = await pool.query('SELECT * FROM customers');
  console.log(results);
})();

npx typeorm@latest init --name typeorm-mysql-test --database mysql

import { DataSource } from 'typeorm';
import { User } from './entity/User';

export const AppDataSource = new DataSource({
  type: 'mysql',
  host: 'localhost',
  port: 3306,
  username: 'root',
  password: 'your_password',
  database: 'practice',
  synchronize: true,
  entities: [User],
  connectorPackage: 'mysql2'
});

import { Entity, PrimaryGeneratedColumn, Column } from 'typeorm';

@Entity()
export class User {
  @PrimaryGeneratedColumn()
  id: number;

  @Column()
  name: string;
}

import { AppDataSource } from './data-source';
import { User } from './entity/User';

AppDataSource.initialize().then(async () => {
  const user = new User();
  user.name = 'Wang';
  await AppDataSource.manager.save(user);

  const users = await AppDataSource.manager.find(User);
  console.log(users);
});