On Wednesday 25 June 2003 20:49, nolan@celery.tssi.com wrote:
> > Well, correct solution is to implement tablespaces on which objects like
> > databases, tables and indexes can be put.
>
> I've not looked at the SQL standard, but it seems to me like the order
> should be:
>
> Databases
> Tablespaces
> Schemas
> Objects (tables, indexes, functions, etc.)
That should be
Tablespaces databases schemas objects
with each of them implemented as a directory and data files under it. If we
could get a quota check propogated in both direction, that would be pretty
good, may be a warning when things start getting close to limit.
> And it really isn't hierarchical. As I understand them (based on my
> Oracle background), tablespaces, unlike schemas, do NOT create a layer
> of data abstraction. That is to say, while the same table name
> can exist in multiple schemas, only one instance of a given table name
> within a given schema can exist, regardless of what tablespace it is in.
Well, if same table name exists in two different databases under same
tablespace, what's the problem?
> Whether or not two databases can share tablespaces isn't clear to me,
> though as a DBA I can think of good reasons why they probably shouldn't
> do so, I'm not sure if that is an absolute.
Well, I would say they should be allowed to.
Shridhar