Re: attisdropped, * expansion and tg_trigtuple - Mailing list pgsql-general

From Nigel J. Andrews
Subject Re: attisdropped, * expansion and tg_trigtuple
Date
Msg-id Pine.LNX.4.21.0306191502400.29248-100000@ponder.fairway2k.co.uk
Whole thread Raw
In response to Re: attisdropped, * expansion and tg_trigtuple  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
On Thu, 19 Jun 2003, Tom Lane wrote:

> "Nigel J. Andrews" <nandrews@investsystems.co.uk> writes:
> > If in a trigger one does a select * from the table the trigger is on
> > is it safe to assume that tg_trigtuple (and so tg_newtuple) will use
> > the same TupleDesc as that returned from the select *, i.e. the
> > tg_relation->rd_att TupleDesc?
>
> Given recent discussions about decoupling logical and physical column
> order, I'd think that assumption might blow up in your face in a version
> or two.  It's unsafe even today if the relation has dropped columns.

Thanks, that's what started me thinking about what I was doing and although I
added a check for attisdropped in my loop it still relies on the trigtuple and
the one returned from select * being the same.

Plus of course I wasn't thinking that at some stage that the logical order
might be changed since I'm not likely to do that, but then one never knows and
someone else might change it.


--
Nigel J. Andrews


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