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IC80529: DB2 OPTIMIZER MIGHT CHOOSE SUB-OPTIMAL INDEX-ORING ACCESS PLAN WHEN ALL RECORDS IN THE TABLE ARE RETURNED.

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • If a query contains only one predicate, an IN predicate, and all
    records in the table qualify the predicate, the optimizer might
    choose an index-oring access plan as in the following example
    query and access plan:
    
    SELECT * FROM FACT WHERE YEAR IN ( 2012, 2013, 2014 );
    
                                     ...
                                    FETCH
                                /-----+------\
                            RIDSCN     TABLE: SCHEMA1
                              |              FACT
                              |
            +-----------------+-----------------+
          SORT              SORT              SORT
            |                 |                 |
          IXSCAN            IXSCAN            IXSCAN
            |                 |                 |
      INDEX: SCHEMA1    INDEX: SCHEMA1    INDEX: SCHEMA1
          INDEX1            INDEX1            INDEX1
    
    If all possible values in the column YEAR are referenced in the
    values list of the IN predicate, then a table-scan access plan
    will be a better choice.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * ALL                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to DB2 version 9.7 Fix Pack 6                        *
    ****************************************************************
    

Problem conclusion

  • Problem was first fixed in DB2 version 9.7 Fix Pack 6
    

Temporary fix

Comments

APAR Information

  • APAR number

    IC80529

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    970

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2011-12-20

  • Closed date

    2012-06-14

  • Last modified date

    2012-11-15

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

    IC80512

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

    IC84580

Fix information

  • Fixed component name

    DB2 FOR LUW

  • Fixed component ID

    DB2FORLUW

Applicable component levels

  • R970 PSN

       UP



Document information

More support for: DB2 for Linux, UNIX and Windows

Software version: 9.7

Reference #: IC80529

Modified date: 15 November 2012