Re: Session optimizer goal and PLSQL

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Wed, 13 Jun 2001 23:28:04 +0100
Message-ID: <992557523.13471.0.nnrp-07.9e984b29@news.demon.co.uk>

This may be a result of the documentation lagging the software. I believe that it is due to the effect of the hidden parameter

_optimizer_force_mode
changing its default from FALSE to TRUE
around version 8.1.7

--
Jonathan Lewis
Yet another Oracle-related web site:  http://www.jlcomp.demon.co.uk

Practical Oracle 8i:  Building Efficient Databases
Publishers:  Addison-Wesley

Reviews at: http://www.jlcomp.demon.co.uk/book_rev.html



Andrew wrote in message <2bfebe60.0106141216.5eee14d0_at_posting.google.com>...


>I use Oracle 8.1.7 EE for NT

>Have database instance optimizer goal=choose, for the session

>first_rows.

>Oracle documentation states:

>"The optimizer goal applies only to queries submitted directly. Use

>hints to determine the access path for any SQL statements submitted

>from within PL/SQL. The ALTER SESSION... SET OPTIMIZER_MODE statement

>does not affect SQL that is run from within PL/SQL."

>

>When I traced my session, trace file shows for all SQL issued from

>PLSQL package optimizer goal inhereted from the session i.e FIRST_ROWS

>(no direct hints on packaged SQL)

>Is it error in documentation or glitch in tkprof? How could I know the

>real execution plan for such PLSQL SQL statements?

Received on Wed Jun 13 2001 - 17:28:04 CDT