I have two columns in my db: start_date and end_date, which are both DATE types. My code is updating the dates as follows:
The accepted answer works only if you want exactly 31 days later. That means if you are using the date "2013-05-31" that you expect to not be in June which is not what I wanted.
If you want to have the next month, I suggest you to use the current year and month but keep using the 1st.
$date = date("Y-m-01");
$newdate = strtotime ( '+1 month' , strtotime ( $date ) ) ;
This way, you will be able to get the month and year of the next month without having a month skipped.