Question

mySQL DB. Its a download log table. A user can download the same file more than once.

I want to select the last 15 unique file downloads by a given user.

So if a users last X downloads are:

UserA, file001, 14.52
UserA, file006, 14.49
UserA, file001, 14.43-Duplicate

I want to select the last x downloads but where the filename is unique, so:

UserA, file001, 14.52
UserA, file006, 14.49

I have the code to select the last 15 downloads, but i don’t know how to apply a group by/distinct to JUST the fileName column:

SELECT `fileName`,`time` FROM `downloads`
WHERE `userName` = 'userA' 
ORDER BY `time` DESC
LIMIT 15

So how do i make sure only unique filenames are returned?

Answer 1

SELECT `fileName`,MAX(`time`) 
FROM `downloads`
WHERE `userName` = 'userA' 
GROUP BY `fileName`
ORDER BY MAX(`time`) DESC
LIMIT 15

A GROUP BY on fileName with MAX on time (to get the last time, to get the first time use MIN) should suffice.