Re: parse error in create index

Stephan Szabo wrote:
> 
> Functional indexes cannot currently take constant values to the function,
> so it's complaining about the constant 'month'.  The current workaround is
> probably to create a function that does the date_part('month', <arg>) for
> you and then use that function in the index creation.

OK, I got it now -- good old pascal/FORTRAN fashion. But now I get

adressen=> CREATE INDEX xxx ON geburtstage (geb_monat(geburtstag));
ERROR:  DefineIndex: (null) class not found
adressen=>

What is a class in this sense, and where can I read about it in the
documentation?
(geburtstag is a row of type DATE in the table geburtstage)

-- 
Hubert Palme
palme@uni-wuppertal.de