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Message Posted: Thu, 04 Aug 2005 @ 18:58:10 GMT


     
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Subj:   Re: Optimizer and Transitive Property of Equality
 
From:   Hassinger, Bill

Although I have not made a study, from experience I have noticed that a centric join order appears to performs more rapidly than a linear join order.

For example

     Where a=b
       And a=c
       And a=d
       And a=e

Is faster than

     Where a=b
       And b=c
       And c=d
       And d=e

Below you indicated adding a=c and time was reduced. What if you removed b=c and only had a=b and a=c? Is the NUSI used then?



     
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