Обсуждение: Planner configuration

I was reading the section about Planner Method Configuration, and I just don't
get why all the options have this message: "This is used for debugging the
query planner". Are they all debugging options, because they don't look like.

http://www.postgresql.org/docs/current/interactive/
->     runtime-config.html#RUNTIME-CONFIG-QUERY

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Martín Marqués        | select 'mmarques' || '@' || 'unl.edu.ar'
Centro de Telematica  |  DBA, Programador, Administrador
             Universidad Nacional
                  del Litoral
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Martin Marques <martin@bugs.unl.edu.ar> writes:
> I was reading the section about Planner Method Configuration, and I just don't
> get why all the options have this message: "This is used for debugging the
> query planner". Are they all debugging options, because they don't look like.

The enable_xxx options are debugging options in the sense that they're
not meant to be used in routine operations.  They are intended to make
it possible to experiment with alternative plan choices --- but ideally
you should be able to get the planner to pick a good plan choice of its
own accord.  You may need to tweak the cost parameters to reflect your
platform more accurately, or you may need to tune some other settings,
or gather more complete data statistics.  If none of this helps it's
grounds for a bug report.

            regards, tom lane