Zammad doesn’t come with an archiving functionality.
We close tickets and that’s if, I mean how would archiving look to you? Everyone I ask gives a complete different answer which proberbly will never lead to a point some one wants.
So, please, describe your use case or your goal. (“I want to archive” is not the complete goal - you want to do that for a specific reason and you also want it in a specific way)
This answer is not easy to answer and depends on a lot of factors.
Usually the answer is “no”, but MySQL is more likely to cause issues because of encodings and when using emoticons for example.
Note that you’ll need to convert your database from postgresql to mysql which is not the easiest step.
Before you ask: This is out of scope for the community.