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PK84125: Improved access control performance on DB2 for z/OS

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Without the "FOR READ ONLY" clause, DB2 considers the SQL
    read-only if it is not update-able. Examples are if there are
    table joins or if there is a sort (for DISTINCT, ORDER BY etc),
    or if the query contains WITH UR or FETCH FIRST. For other
    cases, the SQL is considered "ambiguous" - DB2 cannot determine
    whether the SQL will be updated or not. Certain optimizer
    transformations, such that required for this SQL, are
    dis-allowed for ambiguous SQLs.
    Another way for an ambigious cursor to be considered read-only
    is when the BIND parameter CURRENTDATA is set to NO.
    

Local fix

Problem summary

  • The database optimizer cannot optimize some queries
    efficiently, if he has to prepare for possible subsequent
    updates to the result set.
    

Problem conclusion

  • The affected queries have been extended by clause "FOR READ
    ONLY", so can optimize this query efficiently.
    
    Failing Module(s):
       Database
    
    Affected Users:
       All users
    
    Version Information:
        Portal Version(s): 6.0.1.5
         Pre-Requisite(s):
          Co-Requisite(s): ---
    
        Portal Version(s): 6.1.0.0
         Pre-Requisite(s):
          Co-Requisite(s): ---
    
        Portal Version(s): 6.1.0.1
         Pre-Requisite(s): PK75758
          Co-Requisite(s): ---
    
        Portal Version(s): 6.1.0.2
         Pre-Requisite(s):
          Co-Requisite(s): ---
    
    Platform Specific:
       This fix applies to all platforms.
    
    A fix is available from Fix Central:
    
    http://www.ibm.com/eserver/support/fixes/fixcentral/swgquickorde
    r?apar=PK84125&productid=WebSphere%20Portal&brandid=5
    
    You may need to type or paste the complete address into your Web
    browser.
    

Temporary fix

Comments

APAR Information

  • APAR number

    PK84125

  • Reported component name

    WEBSPHERE PORTA

  • Reported component ID

    5724E7600

  • Reported release

    60J

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2009-04-06

  • Closed date

    2009-05-19

  • Last modified date

    2009-05-19

  • 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

    WEBSPHERE PORTA

  • Fixed component ID

    5724E7600

Applicable component levels

  • R60J PSY

       UP

  • R610 PSY

       UP

  • R61A PSY

       UP

  • R61B PSY

       UP

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSHRKX","label":"WebSphere Portal"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"6.0.1.5","Line of Business":{"code":"LOB31","label":"WCE Watson Marketing and Commerce"}}]

Document Information

Modified date:
21 December 2021