Adam Alkins <[EMAIL PROTECTED]> writes:
> SELECT t.topic_id
> FROM phpbb_topics AS t
> WHERE t.forum_id = 71
> AND t.topic_id NOT IN (205026, 29046,
> 144569, 59780, 187424,
> 138635, 184973, 170551, 22419, 181690, 197254, 205130)
> ORDER BY t.topic_last_post_time
> DESC
> LIMIT 23 OFFSET 0
If you're using 8.1, you'd probably find that an index on (forum_id,
topic_last_post_time) would work nicely for this. You could use it
in prior versions too, but you'd have to spell the ORDER BY rather
strangely:
ORDER BY forum_id desc, topic_last_post_time desc
The reason for this trickery is to get the planner to realize that
the index order matches the ORDER BY ...
regards, tom lane
---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match
