express connect to mongodb code example

Example 1: connect mongo to express api

//using mongoose
npm i mongoose

const mongoose = require("mongoose");

mongoose
  .connect(
    "your mongodb URI",
    {
      useNewUrlParser: true,
      useCreateIndex: true,
      useFindAndModify: false,
      useUnifiedTopology: true,
    }
  )
  .then(() => console.log("mongodb connected"))
  .catch((err) => {
    console.err(err.message);
    process.exit(1);
  });

Example 2: how to access a database in express

var MongoClient = require('mongodb').MongoClient

MongoClient.connect('mongodb://localhost:27017/animals', function (err, client) {
  if (err) throw err

  var db = client.db('animals')

  db.collection('mammals').find().toArray(function (err, result) {
    if (err) throw err

    console.log(result)
  })
})

Example 3: how to access a database in express

var mysql = require('mysql')
var connection = mysql.createConnection({
  host: 'localhost',
  user: 'dbuser',
  password: 's3kreee7',
  database: 'my_db'
})

connection.connect()

connection.query('SELECT 1 + 1 AS solution', function (err, rows, fields) {
  if (err) throw err

  console.log('The solution is: ', rows[0].solution)
})

connection.end()