Re: BIG Joins

In article <30i54i$48v_at_tamsun.tamu.edu> m0v5533_at_tamsun.tamu.edu (Mahesh Vallampati) writes:
>From: m0v5533_at_tamsun.tamu.edu (Mahesh Vallampati)
>Subject: Re: BIG Joins
>Date: 19 Jul 1994 22:19:46 -0500
 

>In article <9407181216.PN01125_at_ll.mit.edu>,
>James Forgy <forgy_at_ll.mit.edu> wrote:
>>In article <305so3$50k_at_panix.com> janest_at_panix.com (John Anest) writes:
>>>From: janest_at_panix.com (John Anest)
>>>In article <9407131738.PN05420_at_LL.MIT.EDU> forgy_at_ll.mit.edu (James Forgy) writes:
>>>>In article <Csw32B.Ju7_at_Unify.com> jde_at_Unify.com (Jeff Evarts) writes:
>>>>I have wrote a 7-Way Join with a Union on a 600,000 row table and it only took
>>>>7 seconds to run.
>>> Unless I'm mistaken, a Union just lumps result sets together. I don't
>>>think its a join!
>>>John
>>Your thoughts don't change reality, you can have a union of many joins...of
>Again These "many joins" must have the same domain and the same number
>of columns.
>>course if I took the union out it would run faster.
>>-jf
>Hie there
>John was write when he said that Union just lump sets together and the
>fact that u mentioned the union there was kinda clouding the issue.

How foolish, if I can do a six-way join in Oracle within two unions (3- joins), this only clarifies that a six-way join can run fast if optimizied...since a union would only slow down the statment speed.

>---------------
>Thanks and Regards
>Mahesh Vallampati
>M.S. In EE
>Dept.of Electrical Engineering,
>Texas A & M University.
>Ph:(409)845-6189
>\\ In the Beginning there was Codd.....
  Received on Thu Jul 21 1994 - 22:26:53 CEST