A fix is available
APAR status
Closed as program error.
Error description
DB2 generates records in SYSIBM.SYSSTATFEEDBACK and/or explain table DSN_STAT_FEEDBACK with REASON='CONFLICT' when there are conflicting statistics. In some cases, DB2 may note the conflict when the discrepancy is small. Since RUNSTATS can be estimated and/or sampled, it is legitimate in some cases that statistics may not be exact.
Local fix
Ignore statistics recommendations with REASON='CONFLICT'.
Problem summary
**************************************************************** * USERS AFFECTED: DB2 11 for z/OS users of * * SYSIBM.SYSSTATFEEDBACK and/or * * DSN_STAT_FEEDBACK * **************************************************************** * PROBLEM DESCRIPTION: DB2 may recommend statistics in * * SYSIBM.SYSSTATFEEDBACK and/or * * DSN_STAT_FEEDBACK with * * REASON='CONFLICT' for small conflicts * * in statistics. * **************************************************************** * RECOMMENDATION: * **************************************************************** DB2 may recommend re-collection of statistics to correct conflicts. These recommendations are marked with REASON='CONFLICT'. In some cases, the conflict is small enough that the potential for improvement in DB2's estimates is low. In these cases, the conflicting statistics should not be recommended. Additional Keywords: SQLPERFORMANCE SQLACCESSPATH SQLSTATS
Problem conclusion
DB2 code has been modified to only recommend re-collection of conflicting statistics when there is a reasonable opportunity to improve DB2's estimates.
Temporary fix
Comments
APAR Information
APAR number
PI15515
Reported component name
DB2 OS/390 & Z/
Reported component ID
5740XYR00
Reported release
B10
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2014-04-08
Closed date
2014-07-23
Last modified date
2014-09-03
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
UI19894
Modules/Macros
DSNXOCCF DSNXOCL DSNXOPRS DSNXOTL
Fix information
Fixed component name
DB2 OS/390 & Z/
Fixed component ID
5740XYR00
Applicable component levels
RB10 PSY UI19894
UP14/08/09 P F408
Fix is available
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Document Information
Modified date:
03 September 2014