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IT17259: QUERY MIGHT TRAP IN DATA PARTITION ELIMINATION OF A ZIGZAG JOIN

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • A query involving zigzag join might result in segmentation
    violation (SEGV) during data partition elimination phase
    (sqlri_datapart_elimination). The stack of the process will
    involve the following functions:
    
           ossDumpStackTraceInternal
           ossDumpStackTraceV98
           OSSTrapFile::dumpEx
           sqlo_trce
           sqloEDUCodeTrapHandler
           _intel_fast_memcmp
           sqlrxcp2
           sqlri_choose_tree_cmp
           sqlri_datapart_elim_evalkey
           sqlri_datapart_elim_set
           sqlri_datapart_elimination
           sqlriZZInit
           sqlriZigZagJoin
           sqlrihsjn
           sqlriSectInvoke
           sqlrr_smp_router
           sqlrr_subagent_router
           sqleSubRequestRouter
           sqleProcessSubRequest
           sqeAgent::RunEDU
           sqzEDUObj::EDUDriver
           sqlzRunEDU
           sqloEDUEntry
           pthread_tryjoin_np
           clone
    
    To temporarily circumvent the issue, you can disable zigzag
    join: DB2_REDUCED_OPTIMIZATION=YES,ZZJN OFF either via db2set or
    via an optimizer profile so that it is applied only for
    this specific query.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * All                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * upgrade to v111 mod 1 fixpack 1 or later                     *
    ****************************************************************
    

Problem conclusion

  • v111 mod 1 fixpack 1 and all future versions will contain the
    fix for this.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT17259

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    B10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2016-09-28

  • Closed date

    2016-12-20

  • Last modified date

    2016-12-20

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

    IT16636

  • 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

[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"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:
29 June 2020