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From Bramandia Ramadhana
Subject Re: Block nested loop join
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Msg-id 700260640810100145k14610225k36e668be18ea6225@mail.gmail.com
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In response to Re: Block nested loop join  (Gregory Stark <stark@enterprisedb.com>)
Responses Re: Block nested loop join
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Thanks for the clarifications.

Just for curiosity, is there any reason of not having block nested-loop join implementation? Is it rarely useful?

As far as I am aware of, in the case of cross product of two tables, block nested-loop join is the most efficient algorithm.

Regards,

Bramandia R.

On Fri, Oct 10, 2008 at 3:30 PM, Gregory Stark <stark@enterprisedb.com> wrote:

Heikki Linnakangas <heikki.linnakangas@enterprisedb.com> writes:

>> Does postgresql support block nested loop join?
>
> Nope.

We do support Hash Join though so I think the only difference is that we can't
use the hash join for cartesian joins.

--
 Gregory Stark
 EnterpriseDB          http://www.enterprisedb.com
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