Re: User-Defined Datatypes

Philip Reimer wrote:

> Hello.
>
> Is it possible to create new structured datatypes in PostgreSQL like in
> this IBM UDB2 statement:


oops, now I'm confused. Was that feature taken out when Postgres

became PostgreSQL? CREATE TYPE speaks only of opaque/scalar types.
I think in PostgreSQL you could use any table as a type name and
the type of a column was then automatically converted into a
foreign key kind of thing. For the sake of portability, I would
actually always prefer that unless the RDBMS provides a feature
to cluster/inline optimize these type tables for the physical
storage. But then, a good RDBMs should have the logical model
independent from physical storage model anyway, but anbout noone
seems to care and everyone continues to bloat the SQL language
with features that should in fact be options of the RDBMS physical
storage manager to (auto-) configure.

So, I guess the answer is no for PostgreSQL. I remember that even
in old Postgres I couldn't actually insert composite data very
easily.

regards
-Gunther




--
Gunther Schadow, M.D., Ph.D.                    gschadow@regenstrief.org
Medical Information Scientist      Regenstrief Institute for Health Care
Adjunct Assistant Professor        Indiana University School of Medicine
tel:1(317)630-7960                         http://aurora.regenstrief.org