Adding from two different fields

[ncjbhd]

Hi,

I'm currently developing a database on my site and I ran into a little bit of a problem. Actually its more of I'm trying to make something more convienient. The database is a list of all the movies that I own and I want to make it so that the field "mplayernum" automatically gets it's number by using the field "mdiscnum" from the previous entry and adds 1. I'm not sure how easy this is, but if anyone can help it would be greatly appriciated.

Thanks