A simple problem with a seemingly complex solution?

AliasZero

Hey there,

I'm writing some forum software and I need to keep track of users viewing threads.

I need to be able to mark each thread as unread or read, depending on whether the user has visited it before the last post was posted or after.

At first I thought I could track the user's time of the user's last view of the forum the thread is in.

The problem there is that if the user views one thread then goes back to the forum, all threads are unread.

Then I thought I could make a new table in the database - something like:

UserID | ThreadID | LastViewtime 
-------+----------+-------------- 
_____1 |______3672|__<timestamp> 
-------+----------+-------------- 
etc.

This would work flawlessly, but when there are 1000 views on one thread, and one million threads, there would be enormous overhead there.

Now I'm thinking of setting a cookie on the user's machine for each thread, then recalling the cookie for that thread when needed.

I'm just not sure how feasable this is. How would I go about saving/restoring ALL these cookies when the user logs in/out without enormous overhead. How slow/annoying/whatever would it be for the user (and the user's browser and computer) to be storing all these cookies?

Can anyone help?

bastien

Cookies are the way to go. Limited to 4 per domain so it won't work as you planned.

Best to set cookie with timestamp and show everything after that timestamp as new(unread)(the onUnload from the previous visit triggers the cookie set).

AliasZero

I'm not quite sure what you mean.

I think the way you said would mean that if I viewed an old thread (lets use some simple timestamps) with a timestamp of 5, then all the posts newer than that in that forum would also set to read?

If you could explain further, it would be appreciated!

bastien

No, when the user visits your site and browses, everything newer than the timestamp on the cookie shows as unread. The cookie records the the time the user closes the browser on your site (either leaves or closes the browser).

When the user shows up again, any posts that where made since that timestamp show up as unread. Its not the thread itself the cookie uses for a timestamp, its just the time at which the user was finished with the site.

So if I visit your site and post in some threads, then I leave at 8pm, a cookie is set for 8pm of that day. When I come back to your site, any new posts made, since 8pm of the previous time I was there, are show as unread.

This the method that phorum.org uses for their forum...maybe dl the code and look at it, or dl several and see how they do it.

ahundiak

Cookies are probably not a real good idea. Eventually a user will read hundreds of threads. Plus, a user may have multiple machines.

If you really want to track by thread then follow your original idea of using a table. You really don't even need a timestamp field. An entry in the table indicates that a thread was viewed. Index it properly and even a few million records won't be a problem.

AliasZero

Ahh, i see!

Thanks so much! I hate it when I know how to code something, but can't work out the actual design of how to do it!

Thanks again!