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System M Derived in SQL Server ?

  • March 21, 2013 at 1:21 am

    #275483

    All,

    I have recently read the below articles.

    http://www.benjaminnevarez.com/2010/06/optimizing-join-orders/

    http://en.wikipedia.org/wiki/Query_optimizer%5B/url%5D

    [quote-0] Most query optimizers determine join order via a dynamic programming algorithm pioneered by IBM's System R database project[citation needed]. [/quote-0]

    how about sqlserver , sybase & oracle?

    [quote-1]

    Historically, System-R derived query optimizers would often only consider left-deep query plans, which first join two base tables together, then join the intermediate result with another base table, and so on. This heuristic reduces the number of plans that need to be considered (n! instead of 4^n)[/quote-1]

    [quote-2]sql server = System-R derived query optimizers ?[/quote-2]

    If System-R is derived on SqlServer, How "Bushy Plan" is implemented in SQL Server? it seems like by-passing the System-R properties?

    [url]http://en.wikipedia.org/wiki/IBM_System_R">https://www.simple-talk.com/sql/performance/join-reordering-and-bushy-plans/

    http://www.benjaminnevarez.com/2010/06/optimizing-join-orders/

    http://en.wikipedia.org/wiki/Query_optimizer%5B/url%5D

    Most query optimizers determine join order via a dynamic programming algorithm pioneered by IBM's System R database project[citation needed].

    how about sqlserver , sybase & oracle?

    Historically, System-R derived query optimizers would often only consider left-deep query plans, which first join two base tables together, then join the intermediate result with another base table, and so on. This heuristic reduces the number of plans that need to be considered (n! instead of 4^n)

    sql server = System-R derived query optimizers ?

    If System-R is derived on SqlServer, How "Bushy Plan" is implemented in SQL Server? it seems like by-passing the System-R properties?

    http://en.wikipedia.org/wiki/IBM_System_R

    I am not that much clear abou System_R. what exactly the role of System_R in DB?

    karthik

  • March 21, 2013 at 3:59 am

    #1599296

    I am eager to now...any inputs?

    karthik

  • March 21, 2013 at 11:29 pm

    #1599669

    The post topic is System-R.

    karthik

  • March 23, 2013 at 11:44 pm

    #1600104

    🙂

    any thoughts?

    karthik

  • March 25, 2013 at 9:48 am

    #1600379

    A good overview of System-R:

    http://www.cs.berkeley.edu/~brewer/cs262/SystemR.pdf

    As to how the System-R design principal rippled through to Oracle and Sybase ( and later SQL Server), I'm afraid I don't have much insight. While a lot of the basic relational principals have remained, the various vendors have differentiated themselves by their optimization and indexing methodologies.

    And then again, I might be wrong ...
    David Webb

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