On Fri, 3 Apr 2009, Matthew Wakeling wrote:
On Fri, 3 Apr 2009, Tom Lane wrote:
Not unless you have sorted the inputs in some way that has more knowledge
than the "equal" operator represents. Otherwise you can have elements drop
out that might still be needed to match to a later left-hand element.
Of course. You certainly have to choose a sort order that works. Sorting by
the start field would be sufficient in this case.
Oh &^%")(!. That algorithm only finds the matches where l1.start >=
l2.start. Yeah, you're quite right.
Matthew
--
And why do I do it that way? Because I wish to remain sane. Um, actually,
maybe I should just say I don't want to be any worse than I already am.
- Computer Science Lecturer
--
Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance
