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IT15056: DB2 MIGHT PRODUCE INCORRECT RESULT WHEN EXECUTING QUERY WITH UNION AND MULTIPLE BASE TABLES

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • DB2 might produce wrong result if the following conditions are
    satisfied:
    1) The query has two or more tables
    2) The query has one or more UNION ALL
    3) There is a distinct on one of the tables
    4) All the tables are joined to the UNION ALL
    5) The UNION ALL has one or more branches returning only one row
    

Local fix

  • Reduce query optimization to 1.
                db2 "SET CURRENT QUERY OPTIMIZATION 1";
                db2 <query to execute>
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * ALL                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to DB2 10.1 Fix Pack 6                               *
    ****************************************************************
    

Problem conclusion

  • First fixed in DB2 10.1 Fix Pack 6
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT15056

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    A10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    YesHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2016-05-03

  • Closed date

    2017-03-02

  • Last modified date

    2017-03-02

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

    IT15033

  • 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

[{"Line of Business":{"code":"LOB10","label":"Data and AI"},"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":"10.1"}]

Document Information

Modified date:
26 September 2021