chaoschick
20 天前
Node.js 中有多个库可以用于连接和操作数据库,最常用的包括以下几个:
1. **MySQL**:
- 使用 `mysql` 或 `mysql2` 库来连接 MySQL 数据库。
- 示例:
```javascript
const mysql = require('mysql2');
const connection = mysql.createConnection({
host: 'localhost',
user: 'yourUsername',
password: 'yourPassword',
database: 'yourDatabase'
});
connection.connect(err => {
if (err) {
console.error('Error connecting to the database:', err);
return;
}
console.log('Connected to the MySQL database.');
});
connection.query('SELECT * FROM yourTable', (err, results) => {
if (err) {
console.error('Error executing query:', err);
return;
}
console.log('Query results:', results);
});
connection.end();
```
2. **PostgreSQL**:
- 使用 `pg` 库来连接 PostgreSQL 数据库。
- 示例:
```javascript
const { Client } = require('pg');
const client = new Client({
host: 'localhost',
user: 'yourUsername',
password: 'yourPassword',
database: 'yourDatabase'
});
client.connect(err => {
if (err) {
console.error('Error connecting to the database:', err);
return;
}
console.log('Connected to the PostgreSQL database.');
});
client.query('SELECT * FROM yourTable', (err, res) => {
if (err) {
console.error('Error executing query:', err);
return;
}
console.log('Query results:', res.rows);
});
client.end();
```
3. **SQLite**:
- 使用 `sqlite3` 库来连接 SQLite 数据库。
- 示例:
```javascript
const sqlite3 = require('sqlite3').verbose();
const db = new sqlite3.Database('./yourDatabase.db');
db.serialize(() => {
db.each('SELECT * FROM yourTable', (err, row) => {
if (err) {
console.error('Error executing query:', err);
return;
}
console.log('Row:', row);
});
});
db.close();
```