Re: logical column ordering

Tomas Vondra wrote:
> On 27.2.2015 20:34, Alvaro Herrera wrote:
> > Tomas Vondra wrote:
> >
> >> I think we could calls to the randomization functions into some of the
> >> regression tests (say 'create_tables.sql'), but that makes regression
> >> tests ... well, random, and I'm not convinced that's a good thing.
> >>
> >> Also, this makes regression tests harder to think, because "SELECT *"
> >> does different things depending on the attlognum order.
> >
> > No, that approach doesn't seem very useful. Rather, randomize the
> > columns in the CREATE TABLE statement, and then fix up the attlognums so
> > that the SELECT * expansion is the same as it would be with the
> > not-randomized CREATE TABLE.
>
> Yes, that's a possible approach too - possibly a better one for
> regression tests as it fixes the 'SELECT *' but it effectively uses
> fixed 'attlognum' and 'attnum' values (it's difficult to randomize
> those, as they may be referenced in other catalogs).

Why would you care what values are used as attnum? If anything
misbehaves, surely that would be a bug in the patch. (Of course, you
can't just change the numbers too much later after the fact, because the
attnum values could have propagated into other tables via foreign keys
and such; it needs to be done during executing CREATE TABLE or
immediately thereafter.)

--
Álvaro Herrera http://www.2ndQuadrant.com/
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