Long polling - Message system

Question

I\'m looking into doing some long polling with jQuery and PHP for a message system. I\'m curious to know the best/most efficient way to achieve this. I\'m basing is off this Sim

Answer 1

Instead of creating a column named last_checked, you could create a column called: checked. If you save all messages in the database, you could update the field in the database. Example:

1. User 1 sends User 2 a message.
2. PHP receives the message using the long-polling system and saves the message in a table.
3. User 2, when online, would send a signal to the server, notifying the server that User 1 is ready to receive messages
4. The server checks the table for all messages that are not 'checked' and returns them.