Unexpected behavior sorting strings

[Jimmy Thrasher]

I'm seeing some unexpected behavior when sorting some strings, and it indicates 
I don't fully understand how postgresql string sorting works.

As I understand it, postgresql sorts strings roughly like strcmp does: 
character by character based on encoding value.

In particular, I'm seeing the following. I would expect "< S" to come first, 
because "<" (0x3c) is less than ">" (0x3e).

```
supercatdev=# select unnest(array['> N', '< S']) as s order by s;
  s
-
 > N
 < S
(2 rows)
```

I've broken this down further:
```
supercatdev=# select '> N' < '< S';
 ?column?
--
 t
(1 row)
```

Am I missing something about how sorting works?

Metadata:
- postgresql 9.5.19, running on Ubuntu 16LTS
- encoding, collate, and ctype are all UTF8 or en_US.UTF-8, as appropriate

Thanks!

Jimmy

Re: Unexpected behavior sorting strings

[Jimmy Thrasher]

Many thanks! That clarifies things well.

Jimmy

On Wed, Apr 8, 2020, at 11:49 AM, Adrian Klaver wrote:
> On 4/8/20 7:35 AM, Jimmy Thrasher wrote:

> > Am I missing something about how sorting works?
> 
> I believe you are looking for 'C' collation:
> 
> test=# select unnest(array[('> N' collate "C") , ('< S' COLLATE "C")]) 
> as s order by s;
> 
>s
> -
>   < S
>   > N
> (2 rows)
> 
> 
> For more information see:
> 
> https://www.postgresql.org/docs/12/collation.html