Edson Richter <edsonrichter(at)hotmail(dot)com> writes:
> If I do apply trim over the substring, no spaces are removed, and I
> cannot understand why.
> ...
> But using the regular expression matching "^\s*" and "\s*$" works, and
> spaces are removed:
I think what this means is that what you say are runs of spaces are no
such thing, but are some other whitespace character(s). Perhaps tabs,
or non-breaking spaces?
regards, tom lane