PHP - Write to database and remove after set time

Basically when a user wishes to recover their password, I generate a hash and store it in a MySQL Database. I do not want this hash to exist forever though, but to be removed from the database after say 5 minutes.

Does anyone know how to do this?

Also if anyone has any ideas about implementing password reco开发者_运维百科very in a different way I would love to hear.

Thanks in advance, Tom.

Next to the hash, store a date with it. Whenever that date is in the past, the recovery key doesn't work anymore.

No need to actually delete the key then

edit based on comments:

You should run a cronjob every now and then. For example once a day, to delete the keys not used, and already expired.

Your best bet would be to install the APC cache (which has many other benefits) and simply set the key-value pair to expire in the desired amount of time.