Re: Noob question - simplist way to store last 4 viewed products?

[Rick James]

You are trying to keep no more than 4 items in the table for each user?

Alas no OFFSET available on DELETE.

DELETE FROM last_viewed
    WHERE mem_id = '$mem_id'
      AND date <=
        ( SELECT date
             FROM last_viewed
             WHERE mem_id = '$mem_id'
             ORDER BY date DESC LIMIT 4,1
        );

I believe this technique has the following features/bugs:
* It will simply do nothing if there are 4 or fewer items.
* It will delete _all_ rows beyond the latest 4.
* It will screw up if you have duplicate dates. This might be resolvable if product_id is unique and in chronological order (replace date with product_id).
* It won't work on 4.0 because of the subquery. (There are workarounds.)