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  • 1.  Pointing Cognos Analytics Database from Teradata to Big query

    Posted 12/02/21 01:05 PM
    Hi All,

    What are the steps involved and in which areas we need to make changes if we want to migrate all the Cognos reports pointing  Teradata database to google Big query database ?
    I have jdbc simba drivers downloaded for Big query but need to understand in which areas we need to point from Teradata to Big query .
    I want all cognos reports to fetch data from Google Big query database instead of Teradata database . 

    Note : We have moved all the data from Teradata to Big query with same table structure.

    Best Regards,
    Pushp Sharma

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    Pushpender Sharma
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  • 2.  RE: Pointing Cognos Analytics Database from Teradata to Big query

    Posted 12/03/21 07:45 AM

    You should start by reviewing.

    Which data types in Teradata were used in Teradata objects, and how they were defined in GBQ.

    There are concepts in Teradata which do not map 1-1 in GBQ re types.

    Ensure you are using >= CA 11.1.7 FP4 

    You may want to see if GBQ have improved the details/scope of any of their "migrating Teradata databases to GBQ".

    While they are focused on database features, they may share insights re SQL difference, that may be of relevance, along with topics such as the alternatives to Teradata AJI etc.



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    NIGEL CAMPBELL
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  • 3.  RE: Pointing Cognos Analytics Database from Teradata to Big query

    Posted 12/03/21 11:00 AM
    Edited by Todd Schuman 12/03/21 11:02 AM
    Hi Pushp,

    We recently migrated a large bank from Teradata to Google BQ.  Here are the high-level steps:

    1 - Create schema/tables/columns exactly as they exist in Teradata. If any of the fields are named differently, reports will fail.  
    2 - Modify or recreate the data source connection previously used for TD to point to the GBQ database. 
    3 - Identify database specific functions from TD that need to be recoded to match the GBQ syntax i.e. TD: ADD_MONTHS() vs GBQ: DATE_ADD(). 

    The challenge is finding out which tables are needed for each package/report and ensuring they are created in GBQ before you convert the data source, as well as determining which reports have functions that are not supported.  This can become extremely difficult to determine with many reports.  The team at Senturus and myself, created a tool to help expose this level of detail.  Here is a link to the case study:

    Accelerating a Cognos Data Storage Migration - Senturus

    Please let me know if I can help answer any other questions you have.

    -Todd




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    Todd Schuman
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  • 4.  RE: Pointing Cognos Analytics Database from Teradata to Big query

    Posted 12/06/21 03:40 AM
    Dear Todd,

    First of all , I thank you for answering my query . This is exactly what we are trying to do. 
    I want to confirm that we have managed to successfully implement first point and second point. 
    I want to understand more on the third point that you shared.
    We have identified the reports and FM packages that needs to migrated to GBQ as Data source. 
    I wish to know if there will be any change required on Framwork Manager for the FM model in order to point them to new data source and how can we point our FM models and reports to new data source which is GBQ .

    Best Regards

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    Pushpender Sharma
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    Original Message


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