IT05462: INCORRECT RESULTS MIGHT BE RETURNED FOR A QUERY INVOLVING AN AGGREGATION FUNCTION AND AN OUTER JOIN OPERATOR

DB2 Version 10.1 Fix Pack 6 for Linux, UNIX, and Windows

APAR status

• Closed as program error.

Error description

• An outer join query may return incorrect results when all of the
  following conditions are satisfied:
  - The registry variable DB2COMPOPT is set to list that includes
  OJLOCALPRDPLANNING either explicitly or implicitly by setting
  the DB2_WORKLOAD registry variable to 1C or PUREDATA_OLAP
  - There is a predicate in the ON clause of the JOIN operator
  that references only columns from the row preserving side of the
  join operands
  - The access plan of the query has a partial GROUP BY operator
  on the row preserving operand of the outer join operator
  

Local fix

• Use the DB2_REDUCED_OPTIMIZATION=NO_PEA registry variable to
  pick plans that avoid the issue.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All                                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to DB2 version 10.1.0.5.                             *
  ****************************************************************
  

Problem conclusion

• The problem is first fixed in DB2 version 10.1.0.5.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

  IT05044

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  DB2 FOR LUW

• Fixed component ID

  DB2FORLUW

Applicable component levels

• RA10 PSN

     UP