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IT22363: SAP: POOR PERFORMANCE WHEN SAP MEMORY TABLE IN JOIN ON COLUMN ORGANIZED TABLES

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Db2 query may show poor performance, when the following
    conditions are met:
    
    1. The query has Left/Right Outer join
    2. There is a join between SAP memory table and tuple preserving
    side of the Outer Join
    3. Outer join is on Column organized tables
    
    Example:
    
    SELECT *FROM ( t1 LEFT OUTER JOIN t2 ON t1.c1 = t2.c1 ),
    TABLE( SAPTOOLS.MEMORY_TABLE( CAST( ? AS BLOB( 2G )) )
    CARDINALITY 1 ) AS "t_00" ( "C_0" INTEGER )
    WHERE t1.c2 = "t_00"."C_0" ;
    
    t1 and t2 are column organized tables in the above query.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * ALL                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to Db2 11.1 Mod 3 Fix Pack 3 or higher               *
    ****************************************************************
    

Problem conclusion

  • First fixed in Db2 11.1 Mod 3 Fix Pack 3
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT22363

  • 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

    2017-09-12

  • Closed date

    2018-03-19

  • Last modified date

    2018-03-19

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

    IT22361

  • 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":"BU048","label":"IBM Software"},"Product":{"code":"SSEPGG","label":"DB2 for Linux, UNIX and Windows"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.1","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}}]

Document Information

Modified date:
19 March 2018