Re: Re: User defined type with text* field

On Sun, 1 Jul 2001, Ken Kachnowich wrote:

> What I want to do is create a Serialize type for storing Java objects.
> The text would be the class name and the Oid would point to the record
> where the object is stored. I need the class name and not the Oid of the
> table because of a problem I have with long class names (> 32
> characters).
>
> If I figure out how to make this a "varlena" value would variable then
> work for the length specification in the create type command?
Bytea/varlena types do not have a length, they are unlimited-length (like
text).

>
> Are there any examples of varlena user types I could look at?
>
> Thanks,
>
> Ken
>
> > Ken K <kenmail(at)telocity(dot)com> writes:
> >> I am trying to create a user defined type with 2 fields
> >> in it, a text* and an Oid. I am not sure what size to
> >> use in the create type command. When I try variable
> >> the back end core dumps. Are there any examples for
> >> doing this sort of thing? Is it even doable?
> >
> >You can't use any kind of pointer in a datatype --- what is it going to
> >point to? There's nothing it could point at that might live as long as
> >the datavalue on disk will.
> >
> >You could embed a TEXT value into a larger varlena value, say
> >
> > <total length word>
> > Oid
> > <text value here, beginning with its own length word>
> >
> >
> > regards, tom lane
>
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