Phil, What OJB doesn't support exactly?
Sylvain -----Message d'origine----- De: Phil Warrick [mailto:[EMAIL PROTECTED]] Date: lundi, 16. d�cembre 2002 17:11 Cc: OJB Users List Objet: Re: OJB and recursive relationship Sylvain, Actually my example wouldn't work for a reference (it needs access to the indirection table "QualifiedARef" and OJB doesn't support this yet AFAIK). A collection in the A class descriptor should work though: <collection-descriptor name="qualifiedARefs" element-class-ref="QualifiedARef" auto-retrieve="true" auto-update="false" indirection-table="QualifiedARef" > <fk-pointing-to-this-class column="QUALIFIEDAREF_PK"/> <fk-pointing-to-element-class column="A_ID_FK"/> </collection-descriptor> Phil Phil Warrick wrote: > Sylvain, > > Something like this? > > <class-descriptor > class="A" > table="A" > > > <field-descriptor id="1" > name="A_id" > column="A_ID_PK" > jdbc-type="INTEGER" > primarykey="true" > autoincrement="true" > /> > <field-descriptor id="2" > name="name" > column="NAME" > jdbc-type="VARCHAR" > /> > <reference-descriptor > name="qualifiedARef" > class-ref="QualifiedARef" > > > <foreignkey field-id-ref="4"/> > </reference-descriptor> > </class-descriptor> > > <class-descriptor > class="QualifiedARef" > table="QualifiedARef" > > > <field-descriptor id="1" > name="qualifiedId" > column="QUALIFIEDAREF_PK" > jdbc-type="INTEGER" > primarykey="true" > autoincrement="true" > /> > <field-descriptor id="2" > name="A_id" > column="A_ID_FK" > jdbc-type="INTEGER" > /> > <field-descriptor id="3" > name="relationInfo" > column="RELATION_INFO" > jdbc-type="VARCHAR" > /> > <reference-descriptor > name="classARef" > class-ref="A" > > > <foreignkey field-id-ref="2"/> > </reference-descriptor> > </class-descriptor> > > Phil > > [EMAIL PROTECTED] wrote: > >> 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 >>>>> >>>>> -- >>>>> To unsubscribe, e-mail: >>>>> <mailto:[EMAIL PROTECTED]> >>>>> For additional commands, e-mail: >>>>> <mailto:[EMAIL PROTECTED]> >>>> >>>> >>>> >>>> >>>> >>>> -- >>>> To unsubscribe, e-mail: >>>> <mailto:[EMAIL PROTECTED]> >>>> For additional commands, e-mail: >>>> <mailto:[EMAIL PROTECTED]> >>>> >>>> >>>> -- >>>> To unsubscribe, e-mail: >>>> <mailto:[EMAIL PROTECTED]> >>>> For additional commands, e-mail: >>>> <mailto:[EMAIL PROTECTED]> >>> >>> >>> >>> >>> >>> -- >>> To unsubscribe, e-mail: >>> <mailto:[EMAIL PROTECTED]> >>> For additional commands, e-mail: >>> <mailto:[EMAIL PROTECTED]> >>> >>> >>> -- >>> To unsubscribe, e-mail: >>> <mailto:[EMAIL PROTECTED]> >>> For additional commands, e-mail: >>> <mailto:[EMAIL PROTECTED]> >> >> >> >> >> >> -- >> To unsubscribe, e-mail: >> <mailto:[EMAIL PROTECTED]> >> For additional commands, e-mail: >> <mailto:[EMAIL PROTECTED]> >> >> >> -- >> To unsubscribe, e-mail: >> <mailto:[EMAIL PROTECTED]> >> For additional commands, e-mail: >> <mailto:[EMAIL PROTECTED]> > > -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
