Re: AW: SQL3 UNDER

Zeugswetter Andreas SB wrote:
>
> > For multiple
> > inheritance, why not just suggest the use of INHERITS, which is
> > already a Postgres language extension for multiple
> > inheritance. UNDER covers
> > the tree/hierarchy situation, so make it only to SQL3 standards.
> > INHERIT fits the clone/copy/inherits situation that, like I've
> > said before, is like starting a new tree.
>
> Imho the difference is so marginal, that I would not like to see two
> different implementations. Informix e.g. took what Illustra had
> for inherits and only changed the keyword to under, which is imho
> what we should do.

Agreed.

> When calling functions with a class argument they do pass all attributes
> of subclasses to it. They use late function binding, so you can define
> different functions for different subclasses having the same name.
> They only show parent columns when doing 'select * from class' that has
> subclasses.

That's what we are planning also, to return all columns current
favourite syntax to use is 'select ** from class', but even it is not
yet implemented.

BTW, does Informix/Illustra do single or multiple inheritance with their
UNDER?

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Hannu