Re: BUG #13789: pg_admin produces table definitiona instead of a view - Mailing list pgsql-bugs

From Alex Maslennikov
Subject Re: BUG #13789: pg_admin produces table definitiona instead of a view
Date
Msg-id CAEt+eeurWBO5jE4Yzsi2G6hp50Yp1-NcLH1aU5=q7Lt-c2FP_A@mail.gmail.com
Whole thread Raw
In response to Re: BUG #13789: pg_admin produces table definitiona instead of a view  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-bugs
Tom,

Thanks for reply. I only noticed this during DB restore process where I was
getting an error on the line "CREATE TABLE my_view ...". From what I see,
this view was never restored.

thanks,
Alex

On Wed, Dec 2, 2015 at 9:42 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:

> amsl.sm@gmail.com writes:
> > I have a view defined with the following sql statement:
>
> > CREATE OR REPLACE VIEW my_view AS
> > (
> >       select  s.id as start_id
> >       from start s
> >       group by s.id
> >       order by start_date desc
> > );
>
> Note that this view definition isn't even legal unless start.id is
> a primary key, otherwise you get
>
> ERROR:  column "s.start_date" must appear in the GROUP BY clause or be
> used in an aggregate function
>
> > When pg_admin exports this view it outputs it as as table not view:
>
> > CREATE TABLE my_view (
> >     start_id integer
> > );
>
> This is not a bug; if you look further down you'll find something like
>
> CREATE RULE "_RETURN" AS
>     ON SELECT TO my_view DO INSTEAD  SELECT s.id AS start_id
>    FROM start s
>   GROUP BY s.id
>   ORDER BY s.start_date DESC;
>
> which converts the table to a view (admittedly in a not-very-obvious way).
> Because of the dependency on start's primary key, the view can't simply
> be defined up at the top of the dump.  This is how pg_dump chooses to
> break the circularity.
>
>                         regards, tom lane
>

pgsql-bugs by date:

Previous
From: Andres Freund
Date:
Subject: Re: BUG #13788: compile error in generic_msvc.h
Next
From: Paul Moore
Date:
Subject: Re: BUG #13788: compile error in generic_msvc.h