Update custom attribute after collection

Hi,

I need to update a custom attribute depending on the value of another custom attribute for an application.

My initial approach to this is would be to have a stored procedure scheduled daily that will read the first custom attribute and depending on the value will update t_av_accounts column corresponding to that custom attribute. While this is the easiest way and even when upgrade safe since the DB gets exported and imported the Store procedure would still remain, I'm not sure if this is advisable.

Is there a better way to do this? 

Please advice.

Thanks.