> w3t_Last can have ALOT of data in it if you have alot of users/forums.
And it can be safely pruned, with the effect that people who haven't been online for longer won't have the post tracking up to date, but this is a small price in comparison to not being able to backup his data base...
DELETE FROM `w3t_Last`
WHERE `L_Last` < ( UNIX_TIMESTAMP( NOW( ) ) -20 *24 *60 *60 )
prunes all entries in last older than 20 days.
