using interval in a query with a column for the interval value?

I am writing a script and I need to output results to a file based on a table where the data to select is based on a ‘last’ date and an ‘interval’.

Essentially

Name

Last_date

Interval

Jed     2005-06-02      30

Tom     2005-08-02      30

Select name

From table1

Where last_date < now() – [[interval days]];

The interval days part is what is stumping me I need to say “now() – interval ’30 days’” but I need to use the interval column.

How do I make this work?

Thanks,

Jed