On Tue, Apr 24, 2012 at 4:17 PM, Robert Haas <robertmh...@gmail.com> wrote: > Based on that, I'm inclined to propose rejiggering things so that the > presorted-input check runs only at the top level, and not during any > recursive steps.
Just a thought. What about running only every nth step. Maybe something like every 4th step. But actually I'm confused. This seems to be misguided to me. Quicksort isn't stable so even if you have a partially sorted data set the recursive partitions are going to be at best partially sorted after a pivot. I haven't walked through it but suspect even your all-but-one-sorted data set is not finding the data sorted in either partition on the next iteration. -- greg -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
