Phil,

Ok but how do you do the self-reference?

Sorry I don't understand.

Sylvain


-----Message d'origine-----
De: Phil Warrick [mailto:[EMAIL PROTECTED]]
Date: lundi, 16. d�cembre 2002 16:43
�: OJB Users List
Objet: Re: OJB and recursive relationship


Sylvain,

Only one A fk is required in the QualifiedARef table:

QualifiedARef
-------------
int qualifiedARef_PK
String relationInfo
int A_id_FK

Phil


 >
[EMAIL PROTECTED] wrote:
> So, more in practise:
> 
> Classes:
> 
> Class A {                                             Classe QualifiedARef {
> int A_id                                              int qualifiedId
> String name                                           A classARef
> QualifiedARef qualifiedARef                   String relationInfo     
> ...                                                   int A_id
> }                                                     ....
>                                                       }
> 
> 
> Relationnal tables:
> 
> A                                             QualifiedARef
> -                                             -------------
> int A_id_PK                                   int qualifiedARef_PK
> String name                                   int A_id_class_ref_FK
>                                               String relationInfo
>                                               int A_id_FK
> 
> 
> Am I on the right way?
> is there a probem in the QualifiedARef table because there are 2 FK for A??
> 
> Thank you
> Regards
> Sylvain
> 
> 
> 
> 
> -----Message d'origine-----
> De: Phil Warrick [mailto:[EMAIL PROTECTED]]
> Date: lundi, 16. d�cembre 2002 15:59
> �: OJB Users List
> Objet: Re: OJB and recursive relationship
> 
> 
> Hi Sylvain,
> 
> Yes, then class A instead has a reference to a class QualifiedARef (or a 
> collection of these).  QualifiedARef holds the relation info and a 
> reference to the target A.  If bidirectionality is important, it can 
> hold a reference to both of the As in the relation.
> 
> Phil
> 
> [EMAIL PROTECTED] wrote:
> 
>>Hi Phil,
>>
>>Thank you for your answer.
>>Is it also possible if you qualified this self reference (add information about 
>relation)?
>>
>>For example if class A have a reference to another instance of class A and this 
>reference has information like reference_name or something like that.
>>
>>Regards
>>Sylvain
>>
>>-----Message d'origine-----
>>De: Phil Warrick [mailto:[EMAIL PROTECTED]]
>>Date: lundi, 16. d�cembre 2002 15:14
>>�: OJB Users List
>>Objet: Re: OJB and recursive relationship
>>
>>
>>Hi Sylvain,
>>
>>OJB handles self references fine.  In other words class A can have a 
>>reference to another instance of class A or a collection of class As. 
>>You may need to make these proxies if the graph is very large and you 
>>need to control the hits to the db.
>>
>>Phil
>>
>>[EMAIL PROTECTED] wrote:
>>
>>
>>>Hello,
>>>
>>>I have a situation with recursive relationship:
>>>
>>>I have a class Software that represents the softwares that could be installed on my 
>machine. Some of these softwares must have other softwares installed before to be 
>able to be installed.
>>>So, I have a recurvive relationship here.
>>>
>>>How do you implement this relationship with OJB?
>>>
>>>Thank you
>>>Sylvain
>>>
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>>
>>
>>
>>
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> 
> 
> 
> 
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