Re: patch adding new regexp functions

On Sat, Feb 17, 2007 at 09:02:24AM +0100, Peter Eisentraut wrote:
> Jeremy Drake wrote:
> > In case you haven't noticed, I am rather averse to making this return
> > text[] because it is much easier in my experience to use the results
> > when returned in SETOF rather than text[],
>
> The primary use case I know for string splitting is parsing
> comma/pipe/whatever separated fields into a row structure, and the way
> I see it your API proposal makes that exceptionally difficult.
>
> I don't know what your use case is, though. All of this is missing
> actual use cases.
>
> > While, if you
> > really really wanted a text[], you could use the (fully documented)
> > ARRAY(select resultstr from regexp_split(...) order by startpos)
> > construct.
>
> I think, however, that we should be providing simple primitives that can
> be combined into complex expressions rather than complex primitives
> that have to be dissected apart to get simple results.
>
> > > As for the regexp_matches() function, it seems to me that it
> > > returns too much information at once. What is the use case for
> > > getting all of prematch, fullmatch, matches, and postmatch in one
> > > call?
> >
> > It was requested by David Fetter:
> > http://archives.postgresql.org/pgsql-hackers/2007-02/msg00056.php
> >
> > It was not horribly difficult to provide, and it seemed reasonable
> > to me. I have no need for them personally.
>
> David Fetter has also repeated failed to offer a use case for this,
> so I hesitate to accept this.

What is it about having the whole match, pre-match and post-match
available that you're objecting to? Are you saying there aren't
common uses for any or all of these? Regular expression users use
them all over the place, and adding this capability to SQL seems like
a reasonable next step :)

Cheers,
D
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
phone: +1 415 235 3778 AIM: dfetter666
Skype: davidfetter

Remember to vote!