Querying awr to hunt down source of sql executions

From: Stephens, Chris <Chris.Stephens_at_adm.com>
Date: Wed, 2 Mar 2011 09:26:21 -0600
Message-ID: <D95BD5AFADBB0F4E9BB6C53F14D3A0500503E29532_at_JRCEXC1V1.research.na.admworld.com>

I've got a report I email myself everyday that is a list of the top 10 most frequently executed sql from the previous day according to awr. This has turned up a piece of sql that, according to dba_hist_sqlstat, was/is being executed millions and millions of times each day. I tracked this sql down to user defined function that, until recently was used in several views. I've factored out those function calls and everyone is enjoying the performance benefits. However, the SQL is still showing up in the daily report. The odd thing is that when I go looking for entries in dba_hist_active_sess_history I don't see a single entry with the same module. Given my lack of sanity last Friday with execution plans, I'm hesitant to ask for help before I stare at this for a few more hours but I really don't understand how this can be. I actually trust dba_hist_active_session_history because there is on view left that needs to be re-written but I really don't understand the discrepancy in data between the various awr tables and v$ views.

select sql_id, module, sum(executions_delta)

   from dba_hist_sqlstat
   where module = 'MV Refresh process' and

         action = 'VW_PROJECT_STATUS' and
         snap_id IN (select snap_id from dba_hist_snapshot where end_interval_time BETWEEN TRUNC(SYSDATE -1) AND TRUNC(SYSDATE))

   group by sql_id, module;

SQL_ID                 MODULE                           SUM(EXECUTIONS_DELTA)


-------------           ---------------------------- ---------------------

3r6urw0m13rbn MV Refresh process       6692677

select distinct program, module, action
  from DBA_HIST_ACTIVE_SESS_HISTORY
  where sql_id = '3r6urw0m13rbn' and

        snap_id IN (select snap_id from dba_hist_snapshot where end_interval_time BETWEEN TRUNC(SYSDATE -1) AND TRUNC(SYSDATE));

MODULE                              SQL_ID


------------------------------ -------------

Disco10, PPS_QUERY       3r6urw0m13rbn
MSACCESS.EXE                  3r6urw0m13rbn
                                              3r6urw0m13rbn
DBMS_SCHEDULER           3r6urw0m13rbn

v$active_session_history doesn't turn up anything either and that goes back to yesterday as of 11:45am but according to awr this sql has been executed more than 2.7 million times in the last 90 minutes or so. (snapshots taken every 30 minutes).

select module, sum(executions_delta)

   from dba_hist_sqlstat
   where sql_id = '3r6urw0m13rbn' and

               snap_id IN (select snap_id from dba_hist_snapshot where end_interval_time >= SYSDATE - 1/24)    group by sql_id, module;

MODULE                      SUM(EXECUTIONS_DELTA)


------------------------- ---------------------

MV Refresh process 2727010

Anybody got anything?

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http://www.freelists.org/webpage/oracle-l Received on Wed Mar 02 2011 - 09:26:21 CST