Node.js数据库驱动

安装：npm install mysql2

基本使用

query：执行普通语句

const mysql = require('mysql2')

//1.建立连接
const connection = mysql.createConnection({
  host: 'localhost',
  port: 3306,
  database: 'testsql',
  user: 'root',
  password: '123456'
})

//2.执行操作语句
const statement = 'select * from `student`;'
connection.query(statement, (err, values, fields) => {
  if(err) {
    console.log('查询失败：', err);
    return
  }

  console.log(values);
  console.log(fields);
})

Mysql2 支持预编译语句

execute：执行预处理语句

const mysql = require('mysql2')

//1.建立连接
const connection = mysql.createConnection({
  host: 'localhost',
  port: 3306,
  database: 'testsql',
  user: 'root',
  password: '123456'
})

//2.执行预处理语句
const statement = 'select * from `score` where c_id = ? and s_score > ?;'
connection.execute(statement, [03, 90], (err, values) => {
  if(err) {
    console.log('查询失败：', err);
    return
  }

  console.log(values);
})

连接池使用

const connectionPool = mysql.createPool({
  host: 'localhost',
  port: 3306,
  database: 'testsql',
  user: 'root',
  password: '123456',
  connectionLimit: 5
})

Promise 写法

connectionPool.promise().execute(statement, [03, 90]).then((res) => {
  const [values, fields] = res // 解构res
  console.log(values);
  console.log(fields);
}).catch((err) => {
  console.log(err);
});