Обсуждение: ORDER BY DESC and NULLS LAST by default

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However, if this doesn't work well, you might check your localisation and collation settings as the way a database sorts depends on these settings. They can be changed on OS level, in the database configuration and on session level, but you can also use the COLLATE statement in your query.  I would expect PostgreSQL to override these settings when the ORDER BY …. NULL LAST (or FIRST) clause is used, but since I’ve never used this option, I can’t tell for sure. I have seen on other applications (not postgres) that if OS localisation or collation does not match the applications localisation/collation, things may get messed up. Mostly with special characters, but sometimes with sorting as well. To my experience this seems to be more of an issue on Windows machines than on Linux based machines.

On Fri, 2023-10-27 at 16:16 +0200, Loles wrote:
> Can the server be configured so that the default ORDER BY option is DESC instead of ASC?
>
> And to make it NULLS LAST instead of NULLS FIRST?

That is not simple.

You'd have to create new data types with new operators that do just the
opposite of the normal ones.  I'd advise against it.

Yours,
Laurenz Albe

Loles <lolesft@gmail.com> writes:
> I was really wondering if, just like you can disable autocommit mode in
> PostgreSQL, if you could configure some parameter so that ORDER BY, by
> default, would order DESC instead of ASC.

There is no such setting, and we'd be unlikely to consider adding one.
Bitter experience has taught us that GUC parameters that change query
behavior are usually bad ideas.  Also, the SQL standard says
explicitly that ASC is the default behavior.

            regards, tom lane

Loles <lolesft@gmail.com> writes:
> I was really wondering if, just like you can disable autocommit mode in
> PostgreSQL, if you could configure some parameter so that ORDER BY, by
> default, would order DESC instead of ASC.

There is no such setting, and we'd be unlikely to consider adding one.
Bitter experience has taught us that GUC parameters that change query
behavior are usually bad ideas.  Also, the SQL standard says
explicitly that ASC is the default behavior.

                        regards, tom lane