IBM Support

IT38870: RARE WRONG RESULT IN CDE INDEX CASE WHEN WITH UR IS USED

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Wrong result (lost row) is possible in a rare plan:
    - CDE Table access.
    - WITH UR  is used
    - CDE Table has unique index on the column which is used in a
    predicate
    - Plan picks a different index to use and applies predicate
    after rows are fetched from base table.
    

Local fix

  • Make sure good plan is used: unique index on the column in the
    predicate is picked
    OR
    turn off CDE indexes in the plans:
    db2set -im DB2_REDUCED_OPTIMIZATION="COL_IXSCAN_ALL_V1133 OFF"
    If the registry variable is already set to another value, append
    this new setting to the end of the existing setting, separated
    by a comma (no spaces).
    static packages will need to be re-created
    package cache needs to be flushed.
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * all                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to 11.1.4.7                                          *
    ****************************************************************
    

Problem conclusion

  • Upgrade to 11.1.4.7
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT38870

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    B10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    YesHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2021-10-28

  • Closed date

    2022-04-16

  • Last modified date

    2022-04-20

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

    IT38710

  • 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

  • RB10 PSN

       UP

[{"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SSEPGG","label":"DB2 for Linux- UNIX and Windows"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.1","Line of Business":{"code":"LOB10","label":"Data and AI"}}]

Document Information

Modified date:
04 May 2022