Brain-Dead Sort Algorithm???

This message was sent from Geocrawler.com by "Tim Perdue" <tim@perdue.net>
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In the various versions of Postgres that I've
used, I've just been amazed at how stupid the
sorting process is.

I'm trying to SELECT DISTINCT on a table that is
60MB:

-rw-------   1 postgres postgres 89799976 Dec  2
20:27 pg_sorttemp32736.0
-rw-------   1 postgres postgres 87307680 Dec  2
20:27 pg_sorttemp32736.1
-rw-------   1 postgres postgres 84376872 Dec  2
20:27 pg_sorttemp32736.2
-rw-------   1 postgres postgres 78645944 Dec  2
20:27 pg_sorttemp32736.3
-rw-------   1 postgres postgres 66749412 Dec  2
20:27 pg_sorttemp32736.4
-rw-------   1 postgres postgres 71360512 Dec  2
20:29 pg_sorttemp32736.5
-rw-------   1 postgres postgres 260677944 Dec  2
20:28 pg_sorttemp32736.6


It uses over 1GB of disk space to do that sort,
and it would have used a lot more if I hadn't run
out.

Then it won't fail gracefully, instead of just
hangs and leaves temp files completely filling up
the hard drive.

How can it use 1GB of disk to sort a 60MB file?

Tim


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