Re: Postgres regexp matching failure?

On Tue, 2006-09-05 at 10:21 -0400, Alvaro Herrera wrote:
> Mario Splivalo wrote:
> > On Tue, 2006-09-05 at 08:42 -0500, Aaron Bono wrote:
> > > On 9/5/06, Mario Splivalo <mario(dot)splivalo(at)mobart(dot)hr> wrote:
> > >
> > > pulitzer2=# select 'stop works' ~ '^\s*(?:[\
> > > +|-]|(?:[sS][tT][oO][pP]\b)).*$';
> > > ?column?
> > > ----------
> > > f
> > > (1 row)
> > >
> > > Here, postgres should return true, but it gives me false.
> > >
> > >
> > > \b is a back-space - is that what you are wanting there? If I remove
> > > it I get true.
> >
> > Actually, I'm not sure :) As I've mentioned, python/java/perl do as I
> > expected, postgres on the other hand doesn't. If \b was the backspace,
> > then I'd have trouble with '+mario test', and that one seems to be OK.
>
> No, because the \b is inside the "stop" arm of the |. You need to do
> *both*, double backslashes and get rid of \b (or at least understand
> what you actually mean with it ...)
>

I know this might not be the right place for this question, but, how
come (or better: why?) is above regexp macthed ok (ok as in 'the way I
expected') when employed from java/perl/python?

Mario