Instant notifications like Facebook

Question

I am building a social application and was wondering how facebook achieve their notifications. As you know, facebooks notifications are instant. As soon as someone takes an

Answer 1

You might want to take a look at http://nodejs.org/ - it is an event-driven model which is perfectly ideal for a 'social network' / instant notifications scenario.

FYI: You also might find that using a non-SQL database such as MongoDB (http://www.mongodb.org/) will be a lot faster when querying from the DB since each 'person' object in a social network scenario has his/her own unique attributes - which in a normal SQL database is hard to design.