建立mysql連接最基本的步驟

//1. 引入mysql模塊
const mysql = require('mysql');

//2. 設置數據庫配置，四個基本參數要有
const db = {
    host: 'localhost',
    user: 'root',
    password: 'pwd',
    database: 'mydb'
};

//3. 實例化連接，利用createConnection()方法
const connection = mysql.createConnection(db);

//4. 建立連接
connection.connect();

//5. 利用Promise創建api，增刪改查
const readSql = "SELECT * FROM mydb.table;"

const read = () => {
    return new Promise(resolve => {
        connection.query(readSql, (err, result) => {
            if (err) throw err;
            resolve(result);
        });
    });
}

//6. 導出api
module.exports = { read };  //read是個方法，必須加大括號。