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JR23242: PERFORMANCE PROBLEM, PUSHDOWN DOES NOT HAPPEN WITH CORRELATED "IS NULL".

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • In federated environment, if correlated "IS NULL" or "IS NOT
    NULL" in the
    where clause, pushdown will not happen, leads to performance
    problem.
    
    Example query:
    
    UPDATE DB2EDAM.PEOPLE$ P SET MIDDLE_NAME_ALT = (SELECT LOWER(MI)
    FROM
    DB2EDAM.TEMP_CONTACTS$ WHERE P.CONTACT_ID = CONTACT_ID)
            WHERE EXISTS (SELECT 1 FROM DB2EDAM.TEMP_CONTACTS$ T
    WHERE
    T.CONTACT_ID = P.CONTACT_ID
            AND T.ACCOUNT_ID = 'UPD' AND (LOWER(T.MI) <>
    SUBSTR(P.MIDDLE_NAME_ALT,1,1) OR (P.MIDDLE_NAME_ALT IS NULL AND
    T.MI IS
    NOT NULL))
     AND T.CUSTOMER_ID = '10002283');
    

Local fix

  • N/A
    

Problem summary

  • In federated environment, if correlated "IS NULL" or "IS NOT
    NULL" in the
    where clause, pushdown will not happen, leads to performance
    problem.
    

Problem conclusion

  • first fixed in 8.2.FP12
    

Temporary fix

  • N/A
    

Comments

APAR Information

  • APAR number

    JR23242

  • Reported component name

    WS II DRDA WRAP

  • Reported component ID

    5724C7406

  • Reported release

    820

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2006-02-06

  • Closed date

    2006-05-15

  • Last modified date

    2006-05-15

  • 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

    WS II DRDA WRAP

  • Fixed component ID

    5724C7406

Applicable component levels

  • R810 PSN

       UP

  • R820 PSN

       UP

[{"Line of Business":{"code":"LOB10","label":"Data and AI"},"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SS2K5T","label":"InfoSphere Federation Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"820"}]

Document Information

Modified date:
06 October 2021