| Site.aggregate() | |
| .lookup({ | |
| from: 'pages', | |
| localField: '_id', | |
| foreignField: 'siteID', | |
| as: 'pages', | |
| }) | |
| .addFields({ pageCount: { $size: '$pages' } }) // add pageCount field | |
| .project({ pages: 0 }) // exclude pages array | |
| .exec(); |
| const someFunction = async () => { | |
| try { | |
| // wait 5 sec before sending the response | |
| await new Promise(resolve => setTimeout(() => resolve(), 5000)); | |
| return res.json({response: 'here'}) | |
| } catch (error) { | |
| // return error | |
| } | |
| } |
| var date = new Date(); | |
| var daysToDeletion = 120; | |
| var deletionDate = new Date(date.setDate(date.getDate() - daysToDeletion)); | |
| printjson(deletionDate); | |
| var db = db.getSiblingDB('db') | |
| db.getMongo().setSlaveOk(); | |
| printjson(db.messages.find({insertDate : {$lt : deletionDate}}).count()); |
| import 'package:flutter/material.dart'; | |
| import 'dart:math'; | |
| class RotatedIcon extends StatelessWidget { | |
| @override | |
| Widget build(BuildContext context) { | |
| return Transform.rotate( | |
| angle: 90 * pi/180, | |
| child: Icon(Icons.flight), | |
| ); |
So you want to write a sync system for a web app with offline and realtime support? Good luck. You might find the following resources useful.
Database in a browser, a spec (Stepan Parunashvili)
What problem are we trying to solve with a sync system?
The web of tomorrow (Nikita Prokopov)