select 1 from dual sorting to disk?

From: NetComrade <andreyNSPAM_at_bookexchange.net>
Date: Mon, 21 Apr 2003 18:38:22 GMT
Message-ID: <3ea438a8.549342453@nyc.news.speakeasy.net>

  1 select extents,sqladdr,sqlhash from v$sort_usage su, v$session s   2* where s.saddr=su.session_addr
SQL> /    EXTENTS SQLADDR SQLHASH
---------- -------- ----------

         1 9FCC6090 1891762568
         1 9FCC6090 1891762568
         1 9FCC6090 1891762568
         1 9EC73B78 1388977235
         1 9FCC6090 1891762568
         1 9FCC6090 1891762568
         1 9FCC6090 1891762568
         1 9FCC6090 1891762568
         1 9FCC6090 1891762568
         1 9FCC6090 1891762568

select sql_text, parsing_user_id from v$sql where address='9FCC6090';

SQL_TEXT                                 PARSING_USER_ID
---------------------------------------- ---------------
SELECT 1 FROM dual                                    23
SELECT 1 FROM dual                                    22
SELECT 1 FROM dual                                    20
SELECT 1 FROM dual                                    22

there are 4 users that execute this statement, but only one of them seems to sort to disk (22, I joined the first query with v$session).

I can't reproduce this via sql*plus.. I tried setting sort_area_size higher to .5M (on session level of app server), but that doesn't help, plus selecting from dual shouldn't sort to disk!

Am I doing something wront? All other statements that sort to disk, seem to be large enough to sort to disk (sort_area_size is set to 128K) This is a production db.
.......
We use Oracle 8.1.7.4 on Solaris 2.7 boxes remove NSPAM to email Received on Mon Apr 21 2003 - 13:38:22 CDT