IBM Support

IT37079: COUNT DISTINCT QUERIES AGAINST COLUMNAR ORGANIZED TABLES COULD RETURN INCORRECT RESULTS

Subscribe to this APAR

By subscribing, you receive periodic emails alerting you to the status of the APAR, along with a link to the fix after it becomes available. You can track this item individually or track all items by product.

Notify me when this APAR changes.

Notify me when an APAR for this component changes.

 

APAR status

  • Closed as program error.

Error description

  • When running count distinct queries against columnar organized
    tables, incorrect results could be returned.
    

Local fix

  • Set the number of CDE threads to 1, as the problem requires 2 or
    more threads to reproduce. This can be done using  several
    approaches:
    1. update db cfg using DFT_DEGREE 1
    2. db2set DB2_CDE_THREAD_COUNT=1
    3. <OPTGUIDELINES><DEGREE VALUE=1/> </OPTGUIDELINES>
    
    Or increase the db cfg SORTHEAP setting to reduce the likelihood
    of
    hitting the problem, as it reduces the amount of spilling.
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * COUNT DISTINCT QUERIES AGAINST COLUMNAR ORGANIZED TABLES     *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description, Please, install the fix.              *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to Db2 11.5.6 or higher                              *
    ****************************************************************
    

Problem conclusion

  • Upgrade to Db2 11.5.6 or higher
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT37079

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    B50

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    YesHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2021-06-01

  • Closed date

    2021-06-17

  • Last modified date

    2021-06-29

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

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

    IT37353

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":"BU029","label":"Software"},"Product":{"code":"SSEPGG","label":"DB2 for Linux- UNIX and Windows"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.5"}]

Document Information

Modified date:
30 June 2021