IBM Support

IT26734: DB2 MAY AVOID CONSIDERING CERTAIN INDEX ACCESS PLANS WHEN FETCH-FIRST-CLAUSE IS PRESENT AND OPTIMIZE-FOR-CLAUSE IS NOT

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APAR status

  • Closed as program error.

Error description

  • The Db2 Optimizer may avoid considering index ORing, index
    ANDing, and list prefetch access plans when compiling a query
    that contains a fetch-first-clause and does not contain an
    optimize-for-clause. This is for queries that would normally
    qualify for these index access types.
    

Local fix

  • To allow the Db2 Optimizer to consider index ORing access
    plans for queries that qualify the conditions above, the
    following registry setting can be used:
    
        DB2_REDUCED_OPTIMIZATION=IXOROFNR
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * ALL                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * To allow the Db2 Optimizer to consider index ORing access    *
    * plans for queries that qualify the conditions above, the     *
    * following registry setting can be used:                      *
    *                                                              *
    *     DB2_REDUCED_OPTIMIZATION=IXOROFNR                        *
    ****************************************************************
    

Problem conclusion

  • See Description
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT26734

  • 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

    2018-10-25

  • Closed date

    2021-03-16

  • Last modified date

    2021-03-16

  • 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":"BU058","label":"IBM Infrastructure w\/TPS"},"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:
04 May 2022