Re: Reuse Database Design with Object Relational Feature ?

From: Lewis C <lewisc_at_excite.com>
Date: Wed, 11 May 2005 20:52:55 GMT
Message-ID: <o1r481h6dq6oio0feq4ecqab2f37fml9g2@4ax.com>

On 11 May 2005 05:08:49 -0700, "Tony Andrews" <andrewst_at_onetel.com> wrote:

>xta..._at_hotmail.com wrote:
>> I read about Object Relational feature in Oracle 8i and later.
>> IS the "database/table Inheritance" is (one of) the objective of
>Object
>> Relational usage in Oracle ?
>>
>> OR what are the cases where Object Relational is appropriate to use ?
>
>There are no known cases when it is appropriate to use Object
>Relational features in database design! I give my reasons for saying
>this here: http://www.dbforums.com/t1154228.html
>
>So far, no one has disagreed...

I have to disagree.

But first, one of the posters in that thread said "Now if they could do polymorphism I might be interested". I just wanted to say that Oracle does do polymorphism. It's documented and it works. About the only real OO feature it can't do is multiple inheritance and I have never needed that in any language. Then again, I don't spend that much time in OO languages.

Anyway, I disagree mainly in two areas. XML and Object Views.

If you are processing XML, not just storing it but storing and manipulating it for the purpose of generating XML, it makes sense to use XML DB which is objects (or can be) under the covers. Using object schemas gives performance benefits in certain cases, particularly the one I just described.

Second, object views are so powerful for use inside and outside the database that it would be a shame to write them off. That is a feature I have used heavily since 8i (and it has gotten a LOT more useful in each version since). It can make your interfaces with external apps much more intuitive for the programmers who are writing them. By that I mean non-oracle programmers, i.e. Java, C++, VB, etc.

Now, I wouldn't design an application schema around OO for any kind of traditional relational database application. I just disagree with the statement that there are no known reasons to use OR in any design. I'm also kind of against absolutes of any kind, though. ;-)

It's funny. I blogged on OO last week and am going to put up a part 2 tomorrow morning.

Anyway, that's my 2 cents.

Lewis

Lewis R Cunningham

Author, ItToolBox Blog: An Expert's Guide to Oracle http://blogs.ittoolbox.com/oracle/guide/

Topic Editor, Suite101.com: Oracle Database http://www.suite101.com/welcome.cfm/oracle

Received on Wed May 11 2005 - 15:52:55 CDT