Hi I'm trying to select from my downloads table users who havent downloaded for 20 mins.

My download table:
userName,fileName,time(timestamp)

(example data)
jeff, 001.jpg, 2011-07-06 16:08:38
barry, 004.jpg, 2011-07-06 16:09:36

Code:
SELECT * FROM 'downloads' WHERE TIMESTAMPDIFF(MINUTE,CURRENT_TIMESTAMP,time)>20;
All the examples of timestampdiff i've found are really complex, can anyone offer any help please?