Re: BUG #8679: Error in regex function

On Fri, December 13, 2013 18:40, Tom Lane wrote:
> spmpro@pochta.ru writes:
>> May be, regex construction (?<=\pattern\) is not support?
>
> It is not.  What we support is documented at
> http://www.postgresql.org/docs/9.2/static/functions-matching.html#FUNCTIONS-POSIX-REGEXP
>
> I have no idea what "(?<=" is supposed to mean --- it's not a standard

FWIW, perl has these; see http://perldoc.perl.org/perlre.html (search for "Look-Around Assertions" ):

   (?<=pattern)   A zero-width positive look-behind assertion

   (?<!pattern)   A zero-width negative look-behind assertion.


It would certainly be nice if these would implemented in postgres...