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IC77589: DB2 CAN GENERATE A SUB-OPTIMAL QUERY PLAN FOR A TABLE THAT HAS 0 ROW YET OCCUPIES MANY EMPTY PAGES

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Sometimes a table can have 0 row yet occupy many empty pages.
    This situation can occur if you delete
    all rows from a table that originally contained a lot of rows,
    and you don't reorg the table afterwards.
    DB2 optimizer can generate a sub-optimal query plan when such a
    table is involved in a SQL statement.
    

Local fix

  • reorg the table
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * All users of version 9.7 on Linux, Unix and Windows          *
    * platforms.                                                   *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * Sometimes a table can have 0 row yet occupy many empty       *
    * pages. This situation can occur if you delete                *
    * all rows from a table that originally contained a lot of     *
    * rows, and you don't reorg the table afterwards.              *
    * DB2 optimizer can generate a sub-optimal query plan when     *
    * such a table is involved in a SQL statement.                 *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to DB2 V97FP5 or higher version                      *
    ****************************************************************
    

Problem conclusion

  • The APAR was fixed on DB2 V97FP5 and higher version
    

Temporary fix

  • Reorg tables that hold empty pages.
    

Comments

APAR Information

  • APAR number

    IC77589

  • 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

    2011-07-18

  • Closed date

    2012-01-02

  • Last modified date

    2012-01-02

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

    IC77468

  • 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

  • R970 PSN

       UP

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Document Information

Modified date:
02 January 2012