Query to remove aged items

[siwis]

I have a table which contains information relating to user sessions, product id's and quantities for a shopping cart system I'm developing.

Now each time a visitor adds a product to their basket, the sessionID, productID and quantity are saved to this table. If they set the product quantity to 0 it deletes the entry in the table.

The problem I have is that when users close their browser without emptying their cart first, these records remain in the database forever more! This I don't want.

It then struck me that each time an item is added to that table, the same script could check for "expired" entires and delete them based upon a timestamp type field which I could add to the table.

So, my question is this: Is there a simple sql query which would filter all items older than a prefixed amount based upon the current timestamp and what data field type should I add to my table to handle this?
Alternatively, is there a better way to achieve this?

[nnichols]

Add a timestamp field that way it will set itself. The query would just be -

DELETE FROM cart WHERE (UNIX_TIMESTAMP()-UNIX_TIMESTAMP(timestamp_field))>3600

this would delete all entries that were older than 1 hour as the difference is in seconds

Hope this helps 😉

[siwis]

You're a star. Many thanks.