How to show unread/read status of forum post's like vbulletin, phpbb, others?

Question

This is the million dollar question, I see it time and time again on here and other php coding related sites and forums but I have NEVER seen an answer to it.

So I sta

Answer 1

More importantly though, the cookie specification says that browsers need only accept 20 cookies per domain. This limit is increased to 50 by Firefox, and to 30 by Opera, but IE6 and IE7 enforce the limit of 20 cookie per domain. Any cookies beyond this limit will either knock out an older cookie or be ignored/rejected by the browser.

Taken from this author's post

I believe for the unread/read status of forum posts should be done through the database. I could not find an example online, but I have read "PHP and MySQL Web Development (4th Edition)" and they have a section devoted to developing your own forum page. They supply example code and explain the process to get it started.

Answer 2

cookie limit in ie :

at most 300 cookies

at most 4096 bytes per cookie (as measured by the size of the characters that comprise the cookie non-terminal in the syntax description of the Set-Cookie header)

at most 20 cookies per unique host or domain name

Answer 3

I don't think they use cookie since that isn't going to persist if you switch computers (unless it's DB-based cookies that some frameworks provide). I'd assume they have a relationship table in the database that keep track of the latest date a user viewed a thread.