Connecting to MySQL in nodejs (detailed tutorial)-JS Tutorial-php.cn

This article mainly introduces the function of connecting to the MySQL database implemented by nodejs, and analyzes the related operation steps and implementation skills of nodejs connection and querying mysql data in the form of examples. Friends in need can refer to the examples of this article

Describes the function of connecting to MySQL database implemented by nodejs. Share it with everyone for your reference, the details are as follows:

1. Runnpm install mysqlin the project directory to install the mysql module for nodejs;

2. Createdb.jsThe module is used to connect to mysql and define the query query method;

var mysql = require('mysql'); // 创建一个数据库连接池 var pool = mysql.createPool({ connectionLimit: 50, host: 'localhost', user: 'admin', password: '123456', database: 'rp-test' }); // SELECT * FROM users // 让我们的方法支持两种模式 // 一种是只传入SQL语句和回调函数 // 一种是传入SQL语句、参数数据、回调函数 exports.query = function (sql, P, C) { var params = []; var callback; // 如果用户传入了两个参数，就是SQL和callback if (arguments.length == 2 && typeof arguments[1] == 'function') { callback = P; } else if (arguments.length == 3 && Array.isArray(arguments[1]) && typeof arguments[2] == 'function') { params = P; callback = C; } else { throw new Error('对不起，参数个数不匹配或者参数类型错误'); } // 如果用户传入了三个参数，那么就是SQL和参数数组、回调函数 // 从池子里面拿一个可以使用的连接 pool.getConnection(function (err, connection) { // Use the connection connection.query(sql, params, function () { // 使用完毕之后，将该连接释放回连接池 connection.release(); callback.apply(null, arguments); }); }); };

Copy after login

3. Query example

var express = require('express'); var db = require('./db'); var router = express.Router(); router.get('/',function(req, res, next){ db.query("select * from app",function(err,result){ //console.log(result); res.send(JSON.stringify (result)); }); }); module.exports=router;

Copy after login

The above is what I compiled for everyone. I hope it will be useful to you in the future. Everyone is helpful.

How to use the loading progress plug-in with pace.js and NProgress.js (detailed tutorial)

In the WeChat applet About the App life cycle (detailed tutorial)

About the use of NProgress.js loading progress plug-in in jQuery

The above is the detailed content of Connecting to MySQL in nodejs (detailed tutorial). For more information, please follow other related articles on the PHP Chinese website!