Re: Composite datatypes, dynamic member fields

> I use inheritance in such a case.
> (see INHERITS in CREATE TABLE)
> Table with common columns as a base class
> and different tables for classes with
> inherited base class.
> Multiple and multilevel inheritanse possible.
The problem in my case is that even a group of objects which belong 
together might not have even one common attribute.

One idea is to implement a . operator on a basic data type and return
the value 
for the corresponding field from the "operator function".
E.g.
"select * from mytable where mytype.mymember='x'"
could call something like
mytype_member_read( mytype, member_name )
but I'm not sure which datatype member_name would be in this case.

Unfortunately I don't have any idea how to handle updates on such fields
with a user defined member access operator yet.

Does anybody have any advice on that?

Robert Staudinger
PS: Please excuse if this explanation doesn't make perfect sense to you
- it's a little hard for me to say in English what I mean.