MySQL query question

[Jack]

ok... I have a little problem.

I want to run a select query. Example:

SELECT DISTICT topic_id
FROM posts
ORDER BY topic_time DESC

now, as expected, the order by doesn' t do anything. (except making the topic id go descending)

but... if i go

SELECT DISTINCT topic_id, topic_time
FROM posts
ORDER BY topic_time DESC

I get the correct sort order, but now i have more than one rows for each topic_id (becuase the topic_time for the topic_id s are different)

So... If you don't get what I said above, I'll try to now explain in just english.

I want to select unique topic_id. However, i want to order them by topic_time. The topic_time for each topic_id is different.

Can anyone help?