Re: eXtreme PostgreSQL using system catalogs (was Turning - Mailing list pgsql-general

We try to make any _meaningful_ system catalog changes into actual SQL
commands.  There is also little guarantee that these queries will be
valid from release to release, so we don't encourage their use.

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Chris Gamache wrote:
>
> There seems to be a TON of functionality accessable by querying and updating
> the system catalogs directly... Has anyone written a practical guide to the
> proper (ab)use and function of the underlying system tables similar to the
> postgresql cookbook? They ARE documented, but there aren't that many cookbook
> entries for nifty tweaks like disabling triggers by telling postgresql there
> are none... (well, there IS a cookbook recipie for that... :) I'm not sure how
> such a document would be organized, or what would constitute a "nifty" feature.
> The SQL for some of the cooler "\" commands in psql can be gleaned by using the
> -E command. Some other "nifties" can also be found by digging through the code.
> Is this a skill reserved only for the eXtreme postgresql hackers, or can
> (should!) mere mortals be given the understanding to push postgresql to its
> limits?
>
> CG
>
> --- Jean-Luc Lachance <jllachan@nsd.ca> wrote:
> > If you look at a pg_dump file, you will find:
> >
> > UPDATE "pg_class" SET "reltriggers" = 0 WHERE "relname" = '<table
> > name>';
> >
> > UPDATE pg_class SET reltriggers = (
> >   SELECT count(*) FROM pg_trigger where pg_class.oid = tgrelid)
> > WHERE relname = '<table name>';
> >
> > The first statemant turn off trigers, the second turns them back on.
> >
> > JLL
> >
> >
> > Adam Witney wrote:
> > >
> > > Never tried this myself but there is an entry in the cookbook pages that,
> > on
> > > the face of it seems to do what you are asking...
> > >
> > >
> > http://www.brasileiro.net:8080/postgres/cookbook/view-one-recipe.adp?recipe_
> > > id=5925
> > >
> > > > On 25 Nov 2002, Glen Eustace wrote:
> > > >
> > > >> Is there a way that all the triggers associated with a table can be
> > > >> turned off ? I would like to be able to bulk load a table ( I have to
> > > >> use inserts not copy ) and I don't want the triggers to fire. Once
> > > >> loaded I want to turn them back on again. This process will be repeated
> > > >> quite often ( during the development phase).
> > >
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