Re: add_missing_from breaks existing views - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: add_missing_from breaks existing views
Date
Msg-id 200510261458.j9QEwUR15641@candle.pha.pa.us
Whole thread Raw
In response to Re: add_missing_from breaks existing views  (Andrew - Supernews <andrew+nonews@supernews.com>)
Responses Re: add_missing_from breaks existing views
List pgsql-hackers
Should we allow CREATE VIEW to run with "add_missing_from = true" until
we fix CREATE VIEW to handle this cleanly?  We emit a warning when we
add a missing FROM too, as I remember.

---------------------------------------------------------------------------

Andrew - Supernews wrote:
> On 2005-10-26, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > Andrew - Supernews <andrew+nonews@supernews.com> writes:
> >> On 2005-10-26, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >>> Uh, no ... the global setting of add_missing_from does *not* tell you
> >>> anything about whether there exist views in the database that were
> >>> created under a different setting.
> >
> >> I realize that; but is it also not the case that someone who creates a
> >> view that requires add_missing_from, and then turns it off, has _already_
> >> broken dump+restore on his own database?
> >
> > No, because we consider that a client-local setting.  This argument is
> > akin to saying that if a client loads some data with client_encoding FOO
> > into a database with server_encoding BAR, we are not responsible for
> > dumping and reloading the data correctly.
> 
> 8.0:
> 
> test=# show add_missing_from;
>  add_missing_from 
> ------------------
>  off
> (1 row)
> 
> test=# set add_missing_from to true;
> SET
> test=# create view v1 as select test.*;
> CREATE VIEW
> test=# \q
> 
> % pg_dump -U pgsql -s -d test | psql -U pgsql -d test2
> 
> [...]
> ERROR:  missing FROM-clause entry for table "test"
> ERROR:  relation "public.v1" does not exist
> 
> Looks broken to me.
> 
> I wasn't arguing that the broken behaviour was correct, merely that it
> exists.
> 
> > In hindsight I think there's no doubt that we blew it in not making
> > ruleutils.c reverse-list implicit RTEs some time ago.
> 
> Obviously. Isn't hindsight wonderful.
> 
> > Pretending it's the user's mistake isn't
> > an answer that fits down my craw very well...
> 
> I'm not claiming it's the user's mistake. My point is that if the user
> did in fact remove add_missing_from after creating views that depend on it,
> then they have already run into a bug.
> 
> -- 
> Andrew, Supernews
> http://www.supernews.com - individual and corporate NNTP services
> 
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--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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