Explain an object-oriented method for a conversion between the E/R diagram

Somebody can explain me with an example an object-oriented method for a conversion between the E/R diagram and a relational database schema.
Thanks,

Hello here are some tips regarding how to convert ERD into Relational objects.
(1) One to many relationships:
One to many relationships can be explained by following example.
Take example of department and Employee. One employee can work in one department only but one department can have more then one employees. In one to many relationship Primary key of One side (here department table) goes to Many side as foreign key (here Employee table).
(2) Many to Many relationships:
Many to many relationships can be explained by following example.
One student can take many subjects and one subject can be taken by more then one student.
In this case one new table emerges which includes Primary keys of both the tables and establish composite primary key. e.g. here if PK of student is student_id and Pk of course is course_id then new table will emerge named (say) student_course with composite primary key of student_id and course_id (student_id and course_id are also foreign keys)
(3) One to One:
Example: A person can have only one tax file number and one tax file number can be allocated to only one person. In this case PK of any table can go to another table as foreign key.
(4) Super class-sub class relationship:
Example: person can be a man or woman. Such kinds of relationships are called super class- sub class relationship. There are many ways to convert such relationship into tables
we can make one table for super class (eg Table Person) and we can put PK of super class in subclass as primary key (eg if person_id is pk of table person then it will go in both sub classes (man, woman) as Pk and it will also be foreign key of the super class (person)
Note: This is just a way to solve super class relationships there are many other ways which you can choose.
Thanks
Ish

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Object-oriented language basics
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Open source my OIOIC, a completely new object-oriented mechanism for t

OIOIC is a completely new object-oriented mechanism for the C programming language.
Using OIOIC, you can describe the flower, birds, grass, insects, trees, houses ...
Using OIOIC, you can describe the elements, atoms, protons, electrons ...
Using OIOIC, you can describe the earth, the sun, the Milky Way galaxy, collapsar ...
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4. OIOIC unifies the norm of components in the Software World;
5. OIOIC unifies the structure of code tree in the Software World;
6. OIOIC unifies the thinking of object-oriented programming in the Software World;
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http://code.google.com/p/oioic/downloads/list
Welcome your advice!

SamC wrote:It is very, very hard to tell if this is spam. Are you an arch user? Do you think that arch users will be interested in this?
Firstly, thank you. But it is not spam! The thinking of object-oriented programming is very important for any programmer. Do not you think so.

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Carole,
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Dear Guru ,
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RECL_SALV_TABLE,
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components, but it seems like that only works one way (bottom-up).
I also know how to make public variables/functions inside the
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-- -- -- Component D
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If I use an event to pass from D to A, it seems as though I
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I have a remote object in Component A that goes out and gets
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Thanks.
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Peter (or anyone else)...
To take this example to the next (albeit parallel) level, how
would you go about creating a class that will let you just
capture/dispatch local data changes? Following along my original
example (Components A-D),let's say that we have this component
architecture:
Component A
--Component B
-- -- Component C
-- -- -- Component D
-- -- Component E
-- -- Comonnent F
How would we go about creating a dispatch scheme for getting
data between Component C and E/F? Maybe in Component C the user
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based on the user). There are no remote methods at play with this
example, just a simple update of a username that's all contained
within the Flex app.
I tried mimicking the technique that we used for the
RemoteObject methods, but things are a bit different this time
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Now, once again, I know that I can bubble that information up
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Here's what I started to come up with so far:
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// Constructor
public function LocalData() {
// ?? does anything go here ??
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public static function getInstance():LocalData {
if( _self == null ) {
_self = new LocalData();
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public static function selectUsername(userObj:Object):void {
dispatchEvent(new CustomEvent(userObj, "selectUsername"));
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LocalData.selectUsername([some object]);
And in the component that wants to listen for the event:
LocalData.getInstance().addEventListener("selectUsername",
selectUsername_Result);
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The problem with this is that when I go to compile it, it
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HTTP post from ABAP using Object Oriented method

Hi ,
I want to call HTTP from ABAP. I came to know that using classes & objects is the best way to fulfill it.
Interface:
xml_document type ref to cl_xml_document
method post_xml_document.
data: client type ref to if_http_client,
xml_response type ref to cl_xml_document.
data: xml_string type string,
xml_xstring type xstring.
data: zsubrc type sy-subrc.
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client->request->set_header_field( exporting name = 'Content-Type' value = 'text/xml' ).
xml_document->render_2_string( exporting pretty_print = 'X' importing stream = xml_string ).
client->request->set_cdata( exporting data = xml_string offset = 0 ).
client->authenticate( exporting proxy_authentication = space username = 'username' password = 'password' ).
client->send( exceptions http_communication_failure = 1 http_invalid_state = 2 ).
client->receive( exceptions http_communication_failure = 1 http_invalid_state = 2 http_processing_failed = 3 ).
xml_xstring = client->response->get_data( ).
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Above code can be used to do my work.
Apart from the code in ABAP, what are the configurational setting that we need to do ?
Thanks,
Shivaa..

>
mohammad afzal wrote:
> apart from usin the code u should have configured the RFC destination
Thats nonsense, create_by_url does not need an rfc connection. TA SICF is correct.

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At present any class could create a Customer of an Employee.
How do I restrict access to the constructors of Customer and Employee only to UserFactory?
I don't want to make both of these classes interfaces (in which case I could just have UserFactory implement both of them).
Here is an example of how they are set up at present:
public abstract class User {
public class Customer extends User{
public Customer{
public class Employee extends User {
public Employee {
public class UserFactory ???? {
private static UserFactory c_userFactory = null;
private UserFactory (){
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//private clone method too
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Oh and I don't want to create two separate factory classes for Employee and Customer. In C++ there is a concept of friend classes that would have worked nicely in this case.
Thanks for any and all suggestions,
Tim

So correct me if I'm wrong but your suggestion would be something along the lines of:
public abstract class User {
public class Customer extends User{
protected Customer(){
public class Employee extends User {
protected Employee (){
public class UserFactory ???? {
private static UserFactory c_userFactory = null;
private UserFactory (){
public UserFactory getInstance(){
//private clone method too
public Customer createCustomer(){
public Employee createEmployee(){
public class AccessForCustomer extends Customer {
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Thanks,
Tim

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Hi everyone,
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Thanks

You can absolutely do work on the frame from the mouse listener--It just needs an instance. i.e.
public class MyMouseListener implements MouseListener {
private MyFrame frame;
public MyMouseListener(MyFrame frame) {
this.frame = frame;
}Does that make sense?
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I cant seem to get by the wait for mouse click, when using go to (marker)
I have a game that I have 2 push buttons one is
on mouseUp me
go to frame 9
end
on mouseUp me
go to frame 29
end
There is a wait to click in between these 2 frames and when I click on the 2nd button to go to frame 29 it stops at the wait to click?
I have tried all these below and cant get past the click to wait?????
go
go to frame
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Think this issue is resolved but to ensure the full answer is available, here it is.
First, it's a bad idea to use the Tempo channel at all. You can use a script to do anything that you can do there. I have Lingo alternates to the Tempo channel at:
http://www.deansdirectortutorials.com/Lingo/tempoLingo.htm
(think I need to update this page though)
So - DO NOT USE the Tempo Channel setting - Wait for Mouse Click or Key Press.
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on exitFrame
go the frame
end
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Next – the following all do the same thing:
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go to “markername”
go “markername”
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or you could use:
_movie.go("dean")
Don’t use
go to marker “markername”
I think that did work at some point but not anymore.
marker can be used as follows:
go marker (-1)
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Well, that gives the detailed answer to your question.
Dean

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Thanks in Advance.

I guess you can check the link
http://forums.sun.com/thread.jspa?forumID=31&threadID=725662 for this.
I have no idea what point you're trying to make by posting a link to that thread.
Again,if someone thinks that something does not exist,what's the point debating on it.There is no point in debating this.
I don't care,Me neither.
tell me the definition,Like I already said many times: there exists no widely accepted definition of what a "pure OO language" is!
So, I ask you yet again: what is YOUR definition of such a thing? ANd don't go posting links to articles or other threads: just explain in your own wording of what YOU think a "pure OO language" is, and I'll answer your question by telling you if Java fits that definition.
search on google,why do you need that are not answers to my questions I see it has no use arguing with you: you don't seem to understand me.
,but more irrelevant questions on my simple question.I see a chain of irrelevant question, starting with your original post.

Explain an object-oriented method for a conversion between the E/R diagram

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