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Home -> Community -> Usenet -> c.d.o.server -> Re: How "deterministic" are EXPLAIN PLAN results?
His information is a little out of date, anyway.
There is a hidden parameter that controls whether the session level optimizer mode is pushed into PL/SQL or not.
Somewhere around 8.1.6/7 its default value was changed from false to true
-- Regards Jonathan Lewis http://www.jlcomp.demon.co.uk The educated person is not the person who can answer the questions, but the person who can question the answers -- T. Schick Jr One-day tutorials: http://www.jlcomp.demon.co.uk/tutorial.html ____UK_______April 22nd ____Denmark__May 21-23rd ____USA_(FL)_May 2nd Three-day seminar: see http://www.jlcomp.demon.co.uk/seminar.html ____UK_(Manchester)_May ____Estonia___June (provisional) ____Australia_June (provisional) ____USA_(CA, TX)_August The Co-operative Oracle Users' FAQ http://www.jlcomp.demon.co.uk/faq/ind_faq.html "Vladimir M. Zakharychev" <bob_at_dpsp-yes.com> wrote in message news:b73k6u$462$1_at_babylon.agtel.net...Received on Thu Apr 10 2003 - 06:46:18 CDT
>
> Actually, what Sybrand probably meant is that the OPTIMIZER_MODE
> setting is ignored in PL/SQL and is always assumed ALL_ROWS.
> But to my knowledge hints are not ignored, so if you hint your
> query with /*+ FIRST_ROWS */, it will be executed in this mode
> by both PL/SQL and SQL engines. By the way, this may not apply
> to 9i since PL/SQL and SQL use the same engine in 9i.
>