Will reusing createPool cause performance issues?

[Am-CGH]

I used a single class in a module to encapsulate all mysql related methods:

const mysql = require("mysql2");
class Mysql {
    $conn = null;
    constructor(){
        this.$conn = mysql.createPool({
            host: "192.168.6.128",
            user: "root",
            password: "root",
            database: "study",
            port: 3306
        });
    }
    async query($sql){
        let $conn = this.$conn.promise();
        let [rows, fields] = await $conn.query($sql);
        return {rows, fields};
    }
}
module.exports = Mysql;

If I instantiate the use in the request, will multiple accesses create multiple connection pools?

app.get("/", async (req, res, next) => {
    let conn = new Mysql;
    conn.query("SELECT 1");
})

[rafipiccolo]

every time you do "new Mysql;" you create a new pool. it's really not the way to go because after 100 calls to the / route you will have 100 pools :)

one solution is to do

module.exports = new Mysql;

That way you'll have only one pool in all your project.