[eluser]jedd[/eluser]
[quote author="andrewtheandroid" date="1257459116"]just a quick one why not store the timestamp of "last login" for the user.. then compare these with the posts' timestamps? only show the ones that are newer than last login.
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The problem with this approach, btw, is that it assumes a person visits each forum, and reads through every message in that forum, on every visit. It also means you have to track when people leave, rather than when they arrive - this is complicated because it's much easier to track when people arrive than when they leave, and consequently that's all most sites bother with.
I also think that it would be harder - though I have not pondered upon this problem very deeply - to design a self-cleaning system using this methodology - I suspect instead you'd end up with lots of cruft, and/or you'd have to run regular clean-up tasks.
