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Message Posted: Thu, 11 Jan 2001 @ 20:47:06 GMT


     
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Subj:   Re: EXPLAIN cost estimates
 
From:   Paul Johnson

I ran an explain today for a simple insert/select on an almost-empty-just-been-installed 5250. The time estimate was 4 minutes to 66 hours 'with no confidence'. Why bother quoting a time range at all if there is known to be no confidence about the guestimate?

I only use explain output to verify the execution path these days. It seems that the time estimates decrease in usefulness as the years pass by...or maybe that's just me!

At least the optimiser gets it wrong far less often these days, and that's what really matters.

Paul Johnson
UK



     
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