I have been writing a small script that is supposed to check the expiration date 30 days prior to that date and send email reminder.

I have a table with column named `'completed'` meaning the date when the course has been finished, completed. Each course is valid for 1 year.

What I have been trying to do is first add one full year to '`completed`' then check if that new date falls exactly 30 days prior to `now().`

Example: the course was finished on 31 Dec 2012. It is valid until 31 Dec 2013, so if `TODAY` is 1 Dec 2013 email reminder should be sent.

I have this little script:

```
 SELECT distinct
     userID
     , completed+INTERVAL 1 YEAR AS expires
   FROM activity
  WHERE completed > NOW() + INTERVAL 30 DAY

```

but obviously it doesn't do the job... 
Could anyone point me into right direction?

Thanks!
Cheers,
Greg