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  • 1.  Loading a replicated table on IDAA

    Posted Wed July 08, 2020 04:12 AM
    Dear all:
    After upgrading from V5 to V7.5.1,  there seems to be some difference for loading a replicated table with lock mode NONE.
    In V5, the reason-code AQT20006E give a clear messages about the requirement.
    However, in V7 the task was run without error code.
    The load_table was performed via stored procedure.  
    Anyone has the same symptom?

    Best Regards.

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    VICTOR HSIAO
    I/T Specialist
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    #Db2forz/OS


  • 2.  RE: Loading a replicated table on IDAA

    Posted Thu July 09, 2020 03:54 AM
    Hi Victor,
    yes, you are right.  In V7 a so-called 'continuous incremental update' method is used which allows that a replicated table can be loaded to the Accelerator without locking it (LOCKMODE TABLE) on the Db2 z/OS side. This means that on Db2 for z/OS applications can continue to change the table by INSERTs, UPDATEs, DELETEs while the table is loaded to the Accelerator. This is an advantage since the applications are not impacted any more by a locked table.
    Any changes on the Db2 for z/OS table while the table is loaded are replicated to the Accelerator as well through a separate mechanism, so you can be sure that all changes are replicated to the Accelerator.
    BTW, even in V5 this 'continuous incremental update' method exists as an additional configurable option in the Configuration Console. In V7 it is the default and only option.
    I hope this helps and let us know if you have further questions.
    Best regards
    Ute Baumbach

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    Ute Baumbach
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    Original Message


  • 3.  RE: Loading a replicated table on IDAA

    Posted Mon July 29, 2024 12:40 PM

    Hello everyone. I was rereading the manual's definition of the stored procedure ACCEL_LOAD_TABLES and about the lock_mode ROW parameter, it says: "This is the recommended choice if incremental updates are enabled for the tables to be loaded.". I was wondering if when loading replicated tables I should keep LOCK=ROW or if I can use NONE (and then, only committed data is loaded into the accelerator-shadow tables).
    Thank you very much, Ute, for your constant generosity.



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    Johnatan Ariotti
    DB2 z/OS Support
    BANCO DO BRASIL
    Brasilia
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    Original Message


  • 4.  RE: Loading a replicated table on IDAA

    Posted Tue July 30, 2024 10:24 AM

    Hi Johnatan, 

    it is better to keep LOCKMODE=ROW. 
    With LOCKMODE=NONE it can happen that the table is fully reloaded although you maybe just wanted to have changed data loaded (DETECT CHANGES = YES). 

    The LOCKMODE=NONE behavior has changed with V7 (compared to V5). 

    You can read about the changed behavior in the release notes of a new maintenance level, e.g. 
    https://www.ibm.com/support/pages/node/7030925, see section "Changed behavior of ACCEL_LOAD_TABLES"
    Or you can read it in the description of ACCEL_LOAD_TABLES (https://www.ibm.com/docs/en/daafz/7.5?topic=procedures-sysprocaccel-load-tables).

    Hope this helps and best regards

    Ute Baumbach



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    Ute Baumbach
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    Original Message