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IT30036: 12.10 SERVER GENERATES SLOW ANSI JOIN QUERY PLAN COMPARING WITH 11.50

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APAR status

  • Closed as program error.

Error description

  • 12.10 server generates slow ANSI join query plan comparing with
    11.50.
    
    Selectivity varies if distributions are present or not.
    
    Related to table reordering with ANSI JOINs. If SQL_FEAT_CTRL2
    bit 0x4 DISABLE_LVL0_REORDER to disable idsdb00505160 is set
    then behavior resembles 11.50
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * Users of IDS prior to 12.10.xC13.                            *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * 12.10 server generates slow ANSI join query plan compared to *
    * 11.50.                                                       *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    

Problem conclusion

  • Fixed in IDS 12.10.xC13.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT30036

  • Reported component name

    INFORMIX SERVER

  • Reported component ID

    5725A3900

  • Reported release

    C10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2019-08-19

  • Closed date

    2019-10-03

  • Last modified date

    2019-10-03

  • 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

    INFORMIX SERVER

  • Fixed component ID

    5725A3900

Applicable component levels

[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSGU8G","label":"Informix Servers"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"C10","Edition":"","Line of Business":{"code":"","label":""}}]

Document Information

Modified date:
03 October 2019