Message-ID: <3DCA94C7.4EA02207@nsd.ca>
Date: Thu, 07 Nov 2002 11:28:55 -0500
From: Jean-Luc Lachance <jllachan@nsd.ca>
MIME-Version: 1.0
To: "Rison, Stuart" <srison@rvc.ac.uk>
Cc: "''pgsql-sql@postgresql.org' '" <pgsql-sql@postgresql.org>,
	"'Josh Berkus '" <josh@agliodbs.com>
Subject: Re: Copying a rowtype variable.
References: <6BD8CE460CC6EE40B83DDFCED609F84B964D55@cmnt4008.rvc.ac.uk>
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I would personnaly like this feature (assigning a composite from another
similar composite) to be added to PLPGSQL. Another nice feature would be
to able to insert a composite into a table without have to name all
atributes.

Just my $.02


"Rison, Stuart" wrote:
> 
> >> 2) I am looking for an elegant way of copying a rowtype variable:
> >>
> >> eg.
> >>
> >> DECLARE
> >>  current_row orf%ROWTYPE;
> >>  previous_row orf%ROWTYPE;
> >> BEGIN
> >>
> >>  LOOP
> >>  -- use cursors or FOR SELECT to get values into current_row
> >>  -- now try this:
> >>
> >>  previous_row = current_row;
> >>  END LOOP;
> >> END;
> >>
> >> Now, as I anticipated, this fails because a rowtype variable is a
> >> composite
> >> variable.  One working alternative is to do:
> >>
> >
> > I haven't tried this.  One thing I notice above is that you're using
> > the equality operator "=" instead of the assignment operator ":="  .
> > Usually Postgres lets you slack on this, but it would be worth trying
> > to see whether that has an effect on the problem.
> >
> 
> Fair point.  But "previous_row := current_row" doesn't work either.
> 
> > Another thing to try is, instead of a simple variable assignment
> >
> > SELECT current_row INTO previous_row;
> >
> > ... and see if that works.
> 
> Well, I had high hopes for that one... but it didn't work either!
> 
> > I'll tinker later today; there has to be a way to do it.
> 
> I'd definitely appreciate further suggestions, but thanks all the same for
> you help.  I have a feeling that you might have to write a PL function to
> perform the operation... but I haven't really thought about it!
> 
> Stuart.
> 
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