Re: Stripping a prefix

On Fri, Aug 25, 2000 at 09:28:59PM -0700, Ian Turner wrote:
> If the string is like `^www\.', then trim `w' and `.'.

But this trims all 'w's and all '.'s, even if the string doesn't start
with 'www.':

select trim(leading 'www.' from 'wfoo');
ltrim
-------
foo
(1 row)

I ended up writing a function to do it, and for the data sets I'm
dealing with, it's fast enough:

CREATE FUNCTION strip_www (text ) RETURNS text AS
'BEGIN
IF position(''www.'' IN $1) = 1 THEN
RETURN substring($1 FROM 5);
ELSE
RETURN $1;
END IF;
END;' LANGUAGE 'plpgsql';
--
Bruce Guenter <bruceg(at)em(dot)ca> http://em.ca/~bruceg/