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Hash join not being used

From: <Dan.Hubler_at_midata.com>
Date: Mon, 26 Jun 2000 08:05:23 -0500
Message-Id: <10540.110403@fatcity.com>


We have a query that is a good candidate for a hash-join operation. As a matter of fact, when we force it to use a hash-type join (with a hint), the
elapsed time of the query goes from 90 minutes to about 2 minutes.

However, we are unable to force it to use a hash-join, without using the hint.

What perplexes us is that a month ago, the query was using a hash-join on its
own, without our intervention.

Any clues as to why the optimizer would change its mind and stop using a hash-join? Received on Mon Jun 26 2000 - 08:05:23 CDT

Original text of this message

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