Re: cursor sharing

  • From: genegurevich@xxxxxxxxxxxxxxxxxxxxx
  • To: oracle-l <oracle-l@xxxxxxxxxxxxx>
  • Date: Tue, 20 Jun 2006 12:46:24 -0500

Yes, you are right. The plan I got from sql_plan is different from the one
I got via explain plan.

thank you

Gene Gurevich
Oracle Engineering
224-405-4079


                                                                           
             "Ghassan Salem"                                               
             <salem.ghassan@gm                                             
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                                       Re: cursor sharing                  
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Well,
you better get the plan from v$sql_plan, as the explain plan does not do
bind-peeking (when you use the cursor_sharing=force setting). so the plan
given by explain can be different from what you have when you actually
execute the statement (depeding on bind values, whether this is the first
time you execute the statement or not , and the presence of histograms)

rgds

On 6/20/06, genegurevich@xxxxxxxxxxxxxxxxxxxxx <
genegurevich@xxxxxxxxxxxxxxxxxxxxx> wrote:
  No. I am using the following to get the explain plan:

  select plan_table_output from
  table(dbms_xplan.display('PLAN_TABLE',null,'ALL')) (found it on metalink)

  thank you

  Gene Gurevich
  Oracle Engineering
  224-405-4079



               "goran
               bogdanovic"
               <goran00@xxxxxxxx
  To
               m>
  genegurevich@xxxxxxxxxxxxxxxxxxxxx

  cc
               06/20/2006 04:20          oracle-l <oracle-l@xxxxxxxxxxxxx >
               AM
  Subject
                                         Re: cursor sharing










  Did you checked in v$sql_plan the real execution plan with
  CURSOR_SHARING_EXACT ?

  genegurevich@xxxxxxxxxxxxxxxxxxxxx wrote:
        Hi all:

        Can someone recommend a good article on the cursor sharing in
  Oracle
        9. I
        just found a query that runs in 5 seconds
         with CURSOR_SHARING_EXACT and in more than 1 hour without it
        (cursor_sharing is set to force on the DB level)

        I'm trying to find out why it happens.

        thank you

        Gene Gurevich


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