Re: BIG Joins

In article <9407131738.PN05420_at_LL.MIT.EDU> forgy_at_ll.mit.edu "James Forgy" writes:

>>I`m curious... how many people out there know of a runtime environment
>>where a "common" operation on a database involves a join of more than,
>>say, 5 tables?
 [snip]
>>Have YOU ever written one?
>>Was it a one-shot or something intended for repeated use?
>>What was it for?

 [snip]
>I have wrote a 7-Way Join with a Union on a 600,000 row table and it only took
>7 seconds to run.

Since we're getting into a mine's bigger than yours debate...

I wrote a query once that could have been expressed as a 14 table join with no self-joins or unions to bolster the numbers. Given that performance was likely to be a problem <g> it was broken down into 4 separate selects each with 6 - 8 tables for the real thing. The application is now live and the screen in daily use.

Regards,

-- 
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Bruce Horrocks
Surrey, England                The Golden Rule is that the person
                               with the gold makes the rules.
bh_at_granby.demon.co.uk
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