Set last tripped/alarm date, or last action date to an item - best practice?

[rossko57]

@halloween

Now i want to make a rule, when some lights are on for a very long time, so they will be switched off.

The usual way would be to start a timer when the lights are switched ON, that when it expires turns the lights OFF. Not really related to storing last timestamp.
See

Design Pattern: Motion Sensor Timer

Edit: Updates for OH 4 Please see Design Pattern: What is a Design Pattern and How Do I Use Them for details on how to use DPs. Problem Statement Many motion detectors only report ON when they detect motion but do not send a corresponding OFF after no motion has been detected after a period of time. In addition, often one wants to control a device like a light for a certain period after the last motion is seen, not after the motion sensor goes to OFF. Therefore one needs to keep a Contact OPEN…

and many similar.