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Re: OODBMS papers needed

in fact it is a bit difficult for an sql programmer like me to understand how I can
get benefit from ozone. as usualy I think in sql.
Can we querry an ozone db with a langage like oql or Xpath.

In fact I use database because of the querry langage.

ciao

Falko Braeutigam a écrit :

> On Tue, 21 Dec 1999, Markus May wrote:
> > Hi once again,
> >
> > I am also a beginner in OODBMS, but I have some questions concerning this
> > concept of ozone. If ozone offers no query, does this mean that all objects
> > have to be in the memory, when I would like to search for a special object?
> Yes, all objects that are access during one database operation have to be in
> memory - but not all at the same time! This is not different from all other
> database systems.
>
> ozone is build on a central activation architecture. This is, database objects
> are activated (and invoked) inside the server VM only. This is different from
> most of the other object database system that I know. They use client side
> caches to activate objects inside the client VM. So they have to transfer the
> objects from the server to client when the objects are invoked. In ozone
> database objects never leave the server VM. So the server can decide which
> objects should be deactivated. This may happen also if the object is currently
> member of a transaction (query).
>
> >
> > Do I have to write my own search algorithm?
> Yes, as you would have to do this for all other (transient) data of your
> program. I can see only very few good reason why we should handle persistent
> data different from transient data. For example: If you have to search
> "transient" data for a special key, then you would use a hastable
> implementation, which you may have written already or found in standard Java
> packages or bought somewhere. So in fact, you need not to write your own search
> algorithms every time you want to search in an OODBMS because all collection
> classes and algoritms that can be used with transient Java objects can be used
> with ozone too. But on the other hand, if you really need a special algorithm
> for a special kind of data, then it is *possible* to implement and use your
> algorithm in ozone. (big advantage over RDBMSs, IMHO)
>
> Falko
> --
> ______________________________________________________________________
> Falko Braeutigam                         mailto:falko@softwarebuero.de
> softwarebuero m&b (SMB)                    http://www.softwarebuero.de

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