Re: BUG #13934: wrong result of split_part with char value

On Tue, Feb 9, 2016 at 8:55 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> Joe Conway <mail(at)joeconway(dot)com> writes:
> > In other words, when you insert ' ' into string1postgres.a3pattern,
> > which is defined as char(15), the single space is trimmed leaving an
> > empty string:
>
> > test=# select '***' || a3pattern || '!!!' from string1postgres;
> > ?column?
> > ----------
> > ***!!!
> > (1 row)
>
> Actually, I believe the space-trimming happens when the char(n) value
> is coerced to type text in preparation for passing it to the || operator
> (which takes text). Since trailing spaces are considered insignificant
> in char(n), whereas they definitely are significant in text, this is a
> reasonable thing to do, at least in some contexts.
>
>
​And in the OP:

​
select split_part(a2,a3pattern,a4field) from string1postgres;

​split_part likewise takes text, not char, and so an implicit conversion
and trimming takes place.

David j.
​