Re: operator classes for index?

Yves Weißig <weissig@rbg.informatik.tu-darmstadt.de> writes:
> again index access methods, can somebody shed some light into operator
> classes for indexes? The documentation is an entry point, but after
> reading I still don't have a clue how exactly they are used and created?
> Perhaps somebody with great knowledge can supply an 101 on opeartor
> classes? Because I keep getting the hint: You must specify an operator
> class for the index or define a default operator class for the data type.

Have you read
http://developer.postgresql.org/pgdocs/postgres/indexes-opclass.html
http://developer.postgresql.org/pgdocs/postgres/xindex.html
and the reference pages for CREATE OPERATOR CLASS/FAMILY?

If it's still not coming together for you, there are numerous examples
of creating operator classes in the contrib modules.  The GIST and GIN
documentation might be relevant as well:
http://developer.postgresql.org/pgdocs/postgres/gist.html
http://developer.postgresql.org/pgdocs/postgres/gin.html
        regards, tom lane