Re: general purpose array_sort

On Sat, Sep 28, 2024 at 7:05 PM Junwang Zhao <zhjwpku@gmail.com> wrote:

> On Sat, Sep 28, 2024 at 10:41 PM jian he <jian.universality@gmail.com>
> wrote:
> >
> > <parameter>dir</parameter> can have only two potential values, make it
> > as a boolean would be more easier?
> > you didn't mention information:  "by default, it will sort by
> > ascending order; the sort collation by default is using the array
> > element type's collation"
> >
> > tuplesort_begin_datum can do null-first, null-last, so the
> > one-dimension array can allow null values.
>
> The following(create extension intarry first) will give an error, I
> keep the same for array_sort.
>
> SELECT sort('{1234234,-30,234234, null}');
>
>
I would suggest accepting:
asc
desc
asc nulls first
asc nulls last *
desc nulls first *
desc nulls last

As valid inputs for "dir" - and that the starred options are the defaults
when null position is omitted.

In short, mimic create index.

David J.