"Adriano dos Santos Fernandes" ...

> Vlad Horsun escreveu:
> > Why ? To introduce external entities in local database we need to at
> > least add some fields into existing RDB$xxx tables. This means that existing
> > drivers and applications can't correctly query new RDB$xxx and must be
> > upgraded : imagine two tables T in two different catalogs : X.T and Y.T
> > (or T@X and T@Y) - existing drivers not know about catalogs and will think
> > database have two tables T.
> >
> > To preserve compatibility we must not extend RDB$xxx and put
> > external entities into some new tables
> I think is wrong to put external metadata in tables, be it the current
> ones or new ones.

We must put it somewhere. And we need to give easy interface to drivers
to retrieve info.

> It should be a system view IMO...

As soon as we give access via SQL to external metadata i have no problem
with view\relation\etc. Just not mix it into existing RDB$xxx and don't move it into
mega-database ;)

What tables would query your system view ?

> AFAIR, Oracle stores only a timestamp of the original object, and the
> timestamp is also in the original database.
>
> If timestamp of object (in "client" and "server" databases of dblink)
> are different, the procedure/trigger are compiled again when executed,
> and if necessary invalidated.

This is depends if remote database have this info. Firebird, as you know,
didn't track such timestamps.

Regards,
Vlad