antosan/nodejs-mysql

Simple example on using NodeJS with MySql

NodeJS + MySql

Using NodeJS with MySql

dev-example.js

Sample code to get started for learning purposes (not fit for production) which connects to the database and performs an SQL query. This runs for standalone connections i.e. one connection at a time (but in reality you may get 100 or even 1000 connections in one particular time and your server should queue the requests if it is not powerful enough to serve them.)

Run

node dev-example.js

prod-example.js

Code for production that tests concurrent users using Pooling. Connection Pooling is a mechanism to maintain a cache of database connections. This way, that connection can be reused after releasing it.

Run

node prod-example.js

Testing concurrency

Install siege

sudo apt-get install siege

Run the following command while the app is running to fire 10 concurrent users for 1 minute.

siege -c10 -t1M http://localhost:3000

The 100-connection limit in code means that if we fire 1000 concurrent users and our MySQL server is configured to handle such traffic at one socket, then it will run and our code will manage the scheduling of concurrent connections. It will serve 100 connections a time but the remaining 900 will be in queue. Thus, the code will not break.

siege -c1000 -t1M http://localhost:3000