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IT25187: UDF FUNCTIONS RUN AGAINST COLUMNAR (BLU) TABLES MIGHT RETURN INCORRECT RESULTS

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • UDF functions run against columnar tables, that are pushed down
    to the columnar engine (i.e. below CTQ in the explain), might
    return incorrect result under rare timing conditions. One of the
    built-in functions that is confirmed to be affected is
    DBMS_UTILITY.GET_HASH_VALUE.
    Problem is specific to Db2 release 11.1 Mod 3 Fix Pack 3.
    

Local fix

  • this internal registry setting will turn off performance
    optimization done in v11 fp3 which is triggering the issue:
    db2set DB2_CDE_FLAGS=288230376151711744
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * ALL                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to Db2 11.1 Mod 4 Fixpack 4 or higher                *
    ****************************************************************
    

Problem conclusion

  • First fixed in Db2 11.1 Mod 4 Fixpack 4
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT25187

  • 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

    2018-05-29

  • Closed date

    2018-11-27

  • Last modified date

    2018-11-27

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

  • 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":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSEPGG","label":"Db2 for Linux, UNIX and Windows"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.1","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}}]

Document Information

Modified date:
27 November 2018