Cron job script logic

Best way to address my quest?

[henry0]

How should I "map" a script that will every 48 hours delete a table content by selecting only users registered more than 48 hours ago.
Be advised that the script will have to “pick and chose” within a multiple users table

I do not look for the script but I look for its logic.

How should I built that script:
Read a created timestamp and del timestamp+48H
Or any other ways?

Thanks

<edit> typo </edit>

[coopster]

That's how I would do it henry0. I would use the server time to establish your starting point and add 48 hours to it during the script that the cron job is calling. Compare that value to the stored values that are older and do the work.