Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

[Anthony W. Youngman]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

In article <i6KBb.11541$4t 2.8346@bignews4 .bellsouth.net> , Corey Brown
<corey@spectrum software.netwri tes

>Because it is evident for anybody with a grasp on data management.

>
This is exactly the type of answer that I would expect from somebody
like Bob B. Why must you guys always answer direct questions with
inappropriate remarks like this. If you have the knowledge and the
ability to express that knowledge to others, why don't you take a
few minutes out to lay down some cold hard facts, instead of just
telling us to go educate ourselves? Why can't you step up to the
role of teacher and start explaining why you "think" one technology
is better than another?

The trouble with those people is that they think mathematics
*determines* the world. They seem incapable of understanding that
mathematics is only of any use when it *describes* the world.

If you're talking SCIENCE, then the big fly in the ointment with using
maths to describe the world is h, the planck constant. As I see it, the
relational database people simply ASSUME that there is no equivalent to
h as far as data is concerned. Experience says that an equivalent
probably does exist.

Cheers,
Wol
--
Anthony W. Youngman - wol at thewolery dot demon dot co dot uk
Witches are curious by definition and inquisitive by nature. She moved in. "Let
me through. I'm a nosey person.", she said, employing both elbows.
Maskerade : (c) 1995 Terry Pratchett

[Anthony W. Youngman]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

In article <e4330f45.03121 20826.6c8d359c@ posting.google. com>, Alfredo
Novoa <alfredo@ncs.es writes

> See my statement above, but yes I do agree with you on this point.
> A lot of this boils down to religious beliefs and unfortunately you
>cannot
> dispose religion with technological fact.

>
>I hope you don't think that math and science are a religions.

Actually, I've heard it argued, LOGICALLY, that Mathematics is the only
religion that can PROVE it is a religion :-)

Mathematics (as in the BELIEF that set theory actually describes the
real world) can be nothing BUT a religion. I have yet to see anybody
even ATTEMPT to provide proof that it actually works, and I've asked
often enough, on these very newsgroups! Its proponents just ASSUME that
it works, without any evidence.

Cheers,
Wol
--
Anthony W. Youngman - wol at thewolery dot demon dot co dot uk
Witches are curious by definition and inquisitive by nature. She moved in. "Let
me through. I'm a nosey person.", she said, employing both elbows.
Maskerade : (c) 1995 Terry Pratchett

[Alfredo Novoa]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

"Bob Badour" <bbadour@golden .netwrote in message news:<ufadndf-Go9oY0SiRVn-iw@golden.net>. ..

"I have a hard time to understand difference and similarities between
Relational database model and the Object-Oriented model. Can somebody
help me with this?"

It is crystal clear. Isn't it?

>
Yes, it is crystal clear to those who comprehend simple written english.

It seems to me that the inability to comprehend simple statemens is a
constant among the advocates of primitive data management approaches.

Also direct him to the subject line that contrasts a model with a
model--well, with an alleged or hypothetical model in any case.

Indeed.

His profound ignorance of fundamentals prevents him from even knowing what
the fundamentals are.

A vicious circle that traps many people.

I hope you don't think that math and science are a religions.

>
To the devoted zealot, there is only religion.

And all knowledge is belief.

Alfredo, you will never reach a person who cannot distinguish between a
property of an implementation and a property of a technology even when
stated explicitly.

I am afraid you are right.

Did we lose anything by moving to an ODBMS, you bet we did. We lost
out ability to run ad-hoc queries against the data.

And you would have a lot to win with a good RDBMS which allows wide
physical independence. You would have the same performance or better,
ad-hoc queries and the rest of the advantages of The Relational Model.
That is what I am trying to say all the time.

>
I am surprised you let the suggestion he lost only one thing stand
unchallenged.

Well, I was trying to reason with him in little steps. Of course they
lost many other things.


Regards
Alfredo

[Craig Tait]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

I dont beleive this is correct as my experience with R83 pick 15 years ago
accesses data using linked chains with a direct reference to Physical
storage location on disk. Anyone who ever had a GFE (Lost chain) will know
this. I have on a few occasions had to go through the physical chains and
repair them. This is primarly why Pick was always so fast using pre
allocated chunks of space on physical disk in a contiguous blocks so related
data is referenced in a continues read primarly on the same sector on Hard
disk. This is why housekeeping file sizing was so important so as not to
have any data fill beyond its allocated file size and flow into overflow
space (kind of a pre allocated area for file fragements on disk).

So I think that this (I might be wrong) proves


"Nobody" <nobody@nowhere .netwrote in message
news:xzbBb.6505 0$_M.317461@att bi_s54...

Relational databases use keys. Object databases use some sort of
pointer to physical storage location.
>
That's all.
>
>
yensao wrote:

Hi,
I have a hard time to understand difference and similarities between
Relational database model and the Object-Oriented model. Can somebody
help me with this?


Thank you in advance.

Yensao

>

[Michael Kuznetsov]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

Hi Yensao,

Relational database model and the Object-Oriented model are kind of
apple and oranges.

Relational model usually uses to design tables of relational database.
Most common language for it is Entity-Relationship diagrams. That
diagrams describes only simple static relations between thinks
(entities).

Object-oriented model often uses UML that consist of 9 types of
diagrams for describing static and dynamic behaviour of system. Most
useful and powerful using of UML is design and documenting system
written on object oriented languages like java or C++. It is possible
to use UML to describe relational database but it looks clumsy.

In fact problem how to strictly much object-oriented and relational
representation is a big unsolved problem in modern compute science.
And now were created some big and difficult for using frameworks that
convert objects to database (in fact implementation of one model to
another). For example Oracle BC4J and TopLink. So both models are
useful but describe very different parts of software systems.

Regards,

Michael
Brainbench MVP for Oracle Programming

http://www.brainbench.com

yensao20032000@ yahoo.com.au (yensao) wrote in message news:<91e71e71. 0312040939.2c90 b9e5@posting.go ogle.com>...

Hi,
I have a hard time to understand difference and similarities between
Relational database model and the Object-Oriented model. Can somebody
help me with this?
>
>
Thank you in advance.
>
Yensao

[Bob Badour]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

Michael,

I strongly suggest you learn some elementary data management before you post
long detailed messages about the subject. Your post reveals profound
ignorance on your part and is full of all too common misconception. You do
everyone a tremendous disfavour by repeating such nonsense.

Although, I can see why you would call yourself a most vociferous person.

plonk

"Michael Kuznetsov" <mvk37@hotmail. comwrote in message
news:a118d09d.0 312302236.6da78 b28@posting.goo gle.com...

Hi Yensao,
>
Relational database model and the Object-Oriented model are kind of
apple and oranges.
>
Relational model usually uses to design tables of relational database.
Most common language for it is Entity-Relationship diagrams. That
diagrams describes only simple static relations between thinks
(entities).
>
Object-oriented model often uses UML that consist of 9 types of
diagrams for describing static and dynamic behaviour of system. Most
useful and powerful using of UML is design and documenting system
written on object oriented languages like java or C++. It is possible
to use UML to describe relational database but it looks clumsy.
>
In fact problem how to strictly much object-oriented and relational
representation is a big unsolved problem in modern compute science.
And now were created some big and difficult for using frameworks that
convert objects to database (in fact implementation of one model to
another). For example Oracle BC4J and TopLink. So both models are
useful but describe very different parts of software systems.
>
Regards,
>
Michael
Brainbench MVP for Oracle Programming

http://www.brainbench.com

>
yensao20032000@ yahoo.com.au (yensao) wrote in message

news:<91e71e71. 0312040939.2c90 b9e5@posting.go ogle.com>...

Hi,
I have a hard time to understand difference and similarities between
Relational database model and the Object-Oriented model. Can somebody
help me with this?


Thank you in advance.

Yensao

[Nobody]

Re: Need help to understand difference, and contrast between Relationaldatab ase model and the Object-Oriented model

You are missing the point. When I said "some sort of physical pointer"
I didn't mean direct file offset: I glossed over this because different
systems implement it differently. You can't apply your one experience
to a whole class of databases; there is no rule saying a database must
exist in one file.

The point of my posting was the static versus dynamic relationships
between objects.


Craig Tait wrote:

I dont beleive this is correct as my experience with R83 pick 15 years ago
accesses data using linked chains with a direct reference to Physical
storage location on disk. Anyone who ever had a GFE (Lost chain) will know
this. I have on a few occasions had to go through the physical chains and
repair them. This is primarly why Pick was always so fast using pre
allocated chunks of space on physical disk in a contiguous blocks so related
data is referenced in a continues read primarly on the same sector on Hard
disk. This is why housekeeping file sizing was so important so as not to
have any data fill beyond its allocated file size and flow into overflow
space (kind of a pre allocated area for file fragements on disk).
>
So I think that this (I might be wrong) proves
>
>
"Nobody" <nobody@nowhere .netwrote in message
news:xzbBb.6505 0$_M.317461@att bi_s54...
>

>>Relational databases use keys. Object databases use some sort of
>>pointer to physical storage location.
>>
>>That's all.
>>
>>
>>yensao wrote:
>>

>>>Hi,
>>>I have a hard time to understand difference and similarities between
>>>Relational database model and the Object-Oriented model. Can somebody
>>>help me with this?
>>>
>>>
>>>Thank you in advance.
>>>
>>>Yensao

>>

>
>

[Michael Kuznetsov]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

Relax pal. So many emotions from a so short message.

I have been working both with object oriented design and database
design 10 years. Sorry if my point of view on this subject is very
different for yours.

Happy New Year!

Mike


"Bob Badour" <bbadour@golden .netwrote in message news:<3vSdnfab7 6NpA2-iRVn-jg@golden.net>. ..

Michael,
>
I strongly suggest you learn some elementary data management before you post
long detailed messages about the subject. Your post reveals profound
ignorance on your part and is full of all too common misconception. You do
everyone a tremendous disfavour by repeating such nonsense.
>
Although, I can see why you would call yourself a most vociferous person.
>
plonk
>
"Michael Kuznetsov" <mvk37@hotmail. comwrote in message
news:a118d09d.0 312302236.6da78 b28@posting.goo gle.com...

Hi Yensao,

Relational database model and the Object-Oriented model are kind of
apple and oranges.

Relational model usually uses to design tables of relational database.
Most common language for it is Entity-Relationship diagrams. That
diagrams describes only simple static relations between thinks
(entities).

Object-oriented model often uses UML that consist of 9 types of
diagrams for describing static and dynamic behaviour of system. Most
useful and powerful using of UML is design and documenting system
written on object oriented languages like java or C++. It is possible
to use UML to describe relational database but it looks clumsy.

In fact problem how to strictly much object-oriented and relational
representation is a big unsolved problem in modern compute science.
And now were created some big and difficult for using frameworks that
convert objects to database (in fact implementation of one model to
another). For example Oracle BC4J and TopLink. So both models are
useful but describe very different parts of software systems.

Regards,

Michael
Brainbench MVP for Oracle Programming

http://www.brainbench.com

yensao20032000@ yahoo.com.au (yensao) wrote in message

news:<91e71e71. 0312040939.2c90 b9e5@posting.go ogle.com>...

Hi,
I have a hard time to understand difference and similarities between
Relational database model and the Object-Oriented model. Can somebody
help me with this?
>
>
Thank you in advance.
>
Yensao

[Alfredo Novoa]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

mvk37@hotmail.c om (Michael Kuznetsov) wrote in message news:<a118d09d. 0401012122.68f2 e9f7@posting.go ogle.com>...

Relax pal. So many emotions from a so short message.
>
I have been working both with object oriented design and database
design 10 years.

It does not mean anything.

>Sorry if my point of view on this subject is very
different for yours.

It is not a point of view issue, your post revealed profound ignorance
on the topic indeed.


Regards
Alfredo

[Bob Badour]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

"Alfredo Novoa" <alfredo@ncs.es wrote in message
news:e4330f45.0 401020312.40a25 a69@posting.goo gle.com...

mvk37@hotmail.c om (Michael Kuznetsov) wrote in message

news:<a118d09d. 0401012122.68f2 e9f7@posting.go ogle.com>...

Relax pal. So many emotions from a so short message.

I twit-filtered the guy so I never saw his response. I find it amusing he
assumes my reply involved any particular emotion. Why is it so difficult for
some people to accept one can dispassionately observe that a vociferous
ignoramus is an ignoramus?

(A word to the wise: Anyone, who puts MVP after his or her name, posts to
stroke his or her own ego and for no other reason.)

[Anthony W. Youngman]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model

In article <gSzIb.703884$T r4.1770994@attb i_s03>, Nobody
<nobody@nowhere .netwrites

>You are missing the point. When I said "some sort of physical pointer"
>I didn't mean direct file offset: I glossed over this because different
>systems implement it differently. You can't apply your one experience
>to a whole class of databases; there is no rule saying a database must
>exist in one file.

Except that in this particular case, what you are thinking of as a file
is actually the entire disk as a raw device ...

Not having any experience of R83 I can't be sure, but I think you'll
find "the database is the computer" :-)

Cheers,
Wol
--
Anthony W. Youngman - wol at thewolery dot demon dot co dot uk
Witches are curious by definition and inquisitive by nature. She moved in. "Let
me through. I'm a nosey person.", she said, employing both elbows.
Maskerade : (c) 1995 Terry Pratchett

[David Horsman]

Re: Need help to understand difference, and contrast between Relational database model and the Object-Oriented model


"Anthony W. Youngman" <thewolery@nosp am.demon.co.ukw rote in message
news:tdAoO4Gsef +$EwA8@thewoler y.demon.co.uk.. .
[snip]

Except that in this particular case, what you are thinking of as a

file

is actually the entire disk as a raw device ...
>
Not having any experience of R83 I can't be sure, but I think you'll
find "the database is the computer" :-)

[snip]

In a sense that it true in that typically the file pointers reside in
a dictionary, the dictionaries reside in a VOC or master dictionary
(the account), and the accounts pointers reside in the system account.
Basically. I believe that is still the strategy of many platforms,
but they also support other file implementations as well. Of course I
have to
wonder if disk fragmentation would not disrupt this as much as frame
overflow. I don't think this is an issue.

However, to my knowledge R83 is a standard for the language and
functionality rather than a definition of how the files are physically
implemented within the system. For instance, our ARev code is R83
compliant, so we don't make use of any of the form / screen generation
features present in ARev. The point to R83 was to extend the platform
independence of the "OS" to the code level.

An example of an R83 issue would be the ability to transfer control
from one program to another in BASIC. A permanent transfer existed
for a long time (as in "CHAIN".) Different platforms developed
various language syntax to temporarily transfer control to another
program and then return control to the original program. This took
the form of a PERFORM or EXECUTE statements with various different
parameters and features that were in need of some standardisation .
This is of course distinct from using a SUBROUTINE CALL (I guess
comparable to using an interface), or a GOSUB (a local function) or
shelling out to the host operating system.

Perhaps wiser soles could expand upon or correct some of this.

Regards, Dave Horsman