Select DISTINCT over two columns

[NZ_Kiwis]

I have a table that's set up similar to this

ID | ParentID | PostedTime

I want to select rows where the ID and ParentID are distinct, so if I have ID 7 parent ID 7's are ignored, I want to then order it by PostedTime

SELECT 
DISTINCT t.ID, t.ParentID
FROM `threads` t 
JOIN `threads_tags_links` l ON t.ID = l.ThreadID

I have this but it does not work

[NogDog]

How about just adding a where clause at the end?

WHERE t.ID != t.ParentID