Re: Empty String Comparison Standard compliant?

On Fri, 30 Jan 2004, Christoph Haller wrote:

> Just a short question (PostgreSQL 7.3.4 on hppa-hp-hpux10.20, compiled by GCC 2.8.1)
>
> SELECT ('' > 'GDMF') ; SELECT ('GDMF' > '');
> ?column?
> ----------
> f
> (1 row)
>
> ?column?
> ----------
> t
> (1 row)
>
> Are these results standard compliant?

I think so in general. If the two lengths are not equal, then
"effectively" the shorter string is replaced by an extended version. If
it's NO PAD (varchar/text for us) the character used is a character that
sorts less than any string. Otherwise (char) it's a space. Then you use
the collating sequence to determine the value of >. Most will put space
before any of GDMF, so the above seems reasonable.