Re: order by

On Thu, May 11, 2023 at 4:43 PM Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com>
wrote:

> On 5/11/23 07:29, Marc Millas wrote:
> > Hi,
> >
> > I keep on investigating on the "death postgres" subject
> > but open a new thread as I don't know if it's related to my pb.
> >
> > I have 2 different clusters, on 2 different machines, one is prod, the
> > second test.
> > Same data volumes.
>
> How can they be sharing the same data 'volume'?
>
roughly: one table is 13080000 lines and the second is 13100000 lines,
the data comes from yet another DB.

> those 2 tables have no indexes. they are used to build kind of aggregates
> thru multiple left joins.
>

> Do you mean you are doing dump/restore between them?
>
no

>
> Postgres version for each cluster is?
> 14.2
>

> >
> > On prod if I do
> > select col_a, count(col_a) from table_a group by col_a order by col_a
> desc,
> > I get the numbers of NULL on top.
> > To get the number of NULL on top on the test db, I have to
> > select col_a, count(col_a) from table_a group by col_a order by col_a
> asc.
> >
> > so, it looks like there is something different within the b-tree
> > operator class of varchar (?!?)
> > between those 2 clusters.
> >
> > What can I check to to explain this difference as, to my understanding,
> > it's not a postgresql.conf parameter.
> >
> > thanks
> >
> > Marc MILLAS
> > Senior Architect
> > +33607850334
> > www.mokadb.com <http://www.mokadb.com>
> >
>
> --
> Adrian Klaver
> adrian(dot)klaver(at)aklaver(dot)com
>
>