[DigitalCrowd]

Well, then you get into having to fetch the current lastpost field of all matching threads and that would be, on larger boards, significant overhead. Now you move away from just searching Sphinx, to now search the database as well, then sorting your resulting arrays and pretty soon... you have a SLOW search again.

After further testing..

I rebuilt my index, search results in order. I did a reply to a post about the third the way down, not using the word "the" (my search word) in it. Now, when I do a search for "the", the third post down is out of order.

The ONLY way for a thread to get bumped up, is if the search word has been used again at a later time in that thread.

The Best way to do search, IMHO is to give more weight to recent threads, but get away from sort by date search results. Even Google doesn't offer this, but we are so accustomed to it in the forum world that getting people to break from it is hard. The best way would be to optimize how Sphinx (or the code that makes the call to Sphinx) weighs results.

I did notice on the Sphinx Forums that the sort mode "SPH_SORT_TIME_SEGMENTS" was made to address this and that if it doesn't work to our liking, it can be modified to perform better. I will have too look into it.

Without adding overhead to the search process, I think the days of instant lastpost sorting are gone, unless you can rebuild your full index every 15 minutes or so and for some people, that index process might last that long or longer.