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IC97775: INSTANCE MIGHT ABEND OR RETURN INCORRECT RESULTS DUE TO AN INCORRECT EXECUTION SECTION FOR STAR JOIN

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • An instance might abend or return incorrect results under some
    very specific access plan conditions.
    
    A typical trap file might show the following functions at the
    top of the stacktrace report:
    
    sqlriREBAL2
    sqldEvalDataPred
    sqldReadTemp
    sqldfrd
    sqldRowFetch
    sqlsfetc
    sqlriFetch
    sqlriNljnNonPiped
    sqlrihsjn
    sqlriSectInvoke
    
    The problem is due to an incorrect buffer location that is being
    accessed.  This can only be confirmed by db2 service personnel
    by examining the "section dump" of the execution plan.  The
    "section dump" is located in the binary dump file.
    
    From an access plan point of view, at least the following
    conditions must be true:
    - There is a star join that has a join of a dimension table
    above the IXAND operator that references the same columns of the
    dimension table that was already accessed in the star join below
    the IXAND operator.  This might also be referred to as a back
    join.
    - The dimension table column that is accessed in the star join
    and also later used in the back join is accessed by the Data
    Sargable Predicate and the column.  The dimension table column
    must also not be added to the Output Stream of the Table Scan.
    

Local fix

  • There is no known workaround for this problem other than to
    force a different access plan to avoid at least one of the above
    conditions.
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * All users                                                    *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to DB2 version 10.1.0.4.                             *
    ****************************************************************
    

Problem conclusion

  • The problem is first fixed in DB2 version 10.1.0.4.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IC97775

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    A10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    YesHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2013-11-19

  • Closed date

    2014-05-08

  • Last modified date

    2014-05-26

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

    IC97290

  • 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

[{"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SSEPGG","label":"Db2 for Linux, UNIX and Windows"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"10.1","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}}]

Document Information

Modified date:
26 May 2014