See the existing docs on EXPLAIN, and papers on the developers site:
http://developer.postgresql.org/index.php
---------------------------------------------------------------------------
Diogo Biazus wrote:
> Hi everybody,
>
> I have some questions about the results in explain.
> I don't know exactly what's the diference between "merge join" and "hash
> join", wich one is faster?
> What is the meaning of the cost number?
> Is there any documentation about this?
>
> Thanks in advance,
>
> --
> Diogo de Oliveira Biazus
> diogo@ikono.com.br
> Ikono Sistemas e Automa??o
> http://www.ikono.com.br
>
>
>
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--
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