|
Problem IC82902
|
Status: Closed |
IMPROVE PARSING ROBUSTNESS FOR OPTIMIZER GUIDELINES |
| product: |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 |
| Problem description: |
Customers that are using optimizer guidelines - to force a
specific query plan - sometimes have observed performance issue
that are caused by a sub optimal access plan. The problem
typically occurs intermittently and can be fixed by
"re-optimizing" the query.
A closer investigation will reveal that the DB2 optimizer might
fail to correctly apply the optimizer guideline with an SQL437W
RC=13.
The best way to verify that you have encountered this APAR is to
get an "explain from section" of the compiled query and to
verify the access plan if the desired optimizer guideline was
applied or not.
This issue is caused by an incorrect parsing of the XML tag that
is used for optimizer guideline. With this APAR we will correct
these problems. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* ALL *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Problem Description above. *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 Version 9.7 Fix Pack 7. *
**************************************************************** |
| Local Fix: |
Submit the query again and ensure it get recompiled/reoptimized
so that a new section will end up in the package cache.
One method to accomplish this would be the "FLUSH PACKAGE CACHE
DYNAMIC ..." statement. |
| available fix packs: |
DB2 Version 9.7 Fix Pack 7 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9a for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
First fixed in Version 9.7 Fix Pack 7. |
| Workaround |
not known / see Local fix |
| BUG-Tracking |
forerunner : APAR is sysrouted TO one or more of the following: IC87286
follow-up : |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 25.04.2012
25.10.2012
25.10.2012 |
| Problem solved at the following versions (IBM BugInfos) |
9.7.FP7
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.7.0.7
|
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