Viktor Rosenfeld <listuser36(at)googlemail(dot)com> writes:
> this looks good, but it does not work with DISTINCT.
> CREATE TYPE annotation AS ( namespace varchar, name varchar, value varchar );
> ERROR: could not identify an equality operator for type annotation
My recollection is you need a complete btree operator class to support
DISTINCT. 8.4 would provide that automatically for composite types,
but in 8.3 you'll have to build it yourself.
> I've also tried [ a hash opclass ]
> But then the error message changes to:
> ERROR: cache lookup failed for operator 34755
That's not what I get when I copy your example, so I think you left
something out.
regards, tom lane