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Posted to ojb-user@db.apache.org by ABOU LINA <am...@gmail.com> on 2006/03/07 20:05:29 UTC

PB behavor of Collection item delete ?

Hi,
in ojb document :
---------------------------------------
Say you use the PB to query an object O that has a collection attribute col
with five
elements a,b,c,d,e. Next you delete Objects d and e from col and store O
again with
PersistenceBroker.store(O);
PB will store the remaining objects a,b,c. But it will not delete d and e !
If you then
requery object O it will again contain a,b,c,d,e !!!
--------------------

i ask if the new version of PB (1.0.4) still behave like this ???

Re: PB behavor of Collection item delete ?

Posted by Armin Waibel <ar...@apache.org>.
Hi,

ABOU LINA wrote:
> Hi,
> 
> ok so, i made DAO implementation with OJB PB in a critical project  and  we
> are in step of delivring some module of the application (the mainly module
> now are developped and tested). my question is :
> 
> 1. what will be the cost of migrating from PB to ODMG. ???

There is no need to completely migrate to ODMG.
For all read-only operations the PB-api can still be used without 
modification.
For all insert/update/delete operations use the ODMG-api. Anyway it is 
possible to use the PB-api within the odmg-api, so there is no need to 
use OQL-queries within odmg-tx
http://db.apache.org/ojb/docu/guides/odmg-guide.html#Access+the+PB-api+within+ODMG

All objects read by the PB instance have to be locked *before* you start 
to modify these objects.
http://db.apache.org/ojb/docu/guides/odmg-guide.html#I+don%27t+like+OQL%2C+can+I+use+the+PersistenceBroker+Queries+within+ODMG

When using OQL-queries by default OJB lock all received objects, see 
'implicit locking' section
http://db.apache.org/ojb/docu/guides/odmg-guide.html#Configuration+Properties
http://db.apache.org/ojb/docu/guides/odmg-guide.html#The+TransactionExt+Interface

But take care not to use PB instances looked up from the PBF within a 
odmg-tx.


> 2. there are some tools making  this  migration easy and fast ???

Sorry, there is no tool. But in the metadata files you only have to 
change the auto-xxx settings of your references
http://db.apache.org/ojb/docu/guides/odmg-guide.html#Specific+Metadata+Settings


> 3. in your opinion, the probleme about deleting collection elements justify
> using ODMG instead of PB ???

This depends on your requirements. If you need this behavior
 >>> we don't
 >>> invoke remove but we construct a new collection and we set it :
 >>> 1. get A from database.
 >>> 2. Collection bCol = new ArrayList();
 >>>     A.setBCollection(bCol);
then you have to use the odmg-api.


> 4. Best practice of ODMG and good examples ??

Have a look in the ODMG tutorial, the odmg-guide and in OJB's test-suite 
classes for the ODMG-api.
http://db.apache.org/ojb/docu/tutorials/odmg-tutorial.html
http://svn.apache.org/viewcvs.cgi/db/ojb/branches/OJB_1_0_RELEASE/src/test/org/apache/ojb/odmg/?rev=378044
Sorry, best practice is missing.

regards,
Armin

> Thanks.
> 
> 
> On 3/9/06, Armin Waibel <ar...@apache.org> wrote:
>> Hi,
>>
>> ABOU LINA wrote:
>>> thank first,
>>>
>>> PersistenceBroker *delete elements* from the database that have been
>> removed
>>> from the collection only if i do this :
>>> for example : A 1:n B
>>> 1. i get A from database using OJB Broker.
>>> 2. i delete one element B from A : A.getBCollection().remove(o);
>>>
>>> in this case yes the PB delete the element from database . but in
>> generale
>>> we don't
>>> invoke remove but we construct a new collection and we set it :
>>> 1. get A from database.
>>> 2. Collection bCol = new ArrayList();
>>>     A.setBCollection(bCol);
>>>
>>> in this case the element that not figure in bCol are not deleted because
>> i
>>> use ArrayList. (in my Application i can't put RemovalAwareList directly
>> There is no need to handle with RemovalAwareList instances in your
>> POJO's. Using type 'List' is sufficient and on insert of new objects you
>> can use ArrayList, so
>>
>>> 2. Collection bCol = new ArrayList();
>>>     A.setBCollection(bCol);
>> is valid when insert new objects.
>> But you are right, when updating objects you have to use
>> Collection.remove(...) method.
>>> 2. i delete one element B from A : A.getBCollection().remove(o);
>> it's not allowed to replace the old List with a sub-List instance.
>>
>>
>>> inorder to keep the application independent of OJB classes ...)
>>>
>>> so what is the solution please ... without using ODMG ?????
>> There is none.
>> That's the main difference between the PB-api and ODMG. The ODMG
>> implementation use a "Unit of work" pattern (object state detection,
>> detection of new/deleted objects) the PB-api does immediately write
>> objects to DB and does not keep the objects state "in mind".
>>
>> For the next major release of OJB we plan to extend the PB-api to
>> support a "unit of work" pattern with locking.
>>
>> regards,
>> Armin
>>
>>> Thanks
>>>
>>> On 3/7/06, Armin Waibel <ar...@apache.org> wrote:
>>>> Hi,
>>>>
>>>> ABOU LINA wrote:
>>>>> Hi,
>>>>> in ojb document :
>>>>> ---------------------------------------
>>>>> Say you use the PB to query an object O that has a collection
>> attribute
>>>> col
>>>>> with five
>>>>> elements a,b,c,d,e. Next you delete Objects d and e from col and store
>> O
>>>>> again with
>>>>> PersistenceBroker.store(O);
>>>>> PB will store the remaining objects a,b,c. But it will not delete d
>> and
>>>> e !
>>>>> If you then
>>>>> requery object O it will again contain a,b,c,d,e !!!
>>>>> --------------------
>>>>>
>>>>> i ask if the new version of PB (1.0.4) still behave like this ???
>>>> Oops! Seems you found some outdated documentation - I will fix this
>> till
>>>> next release.
>>>> With corresponding settings OJB 1.0.4 is able to detect the deleted
>>>> objects of the 1:n reference. More info see
>>>>
>>>>
>> http://db.apache.org/ojb/docu/guides/basic-technique.html#1%3An+auto-xxx+setting
>>>>
>> http://db.apache.org/ojb/docu/guides/advanced-technique.html#which-collection-type
>>>> regards,
>>>> Armin
>>>>
>>>>
>>>>
>>>> ---------------------------------------------------------------------
>>>> To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
>>>> For additional commands, e-mail: ojb-user-help@db.apache.org
>>>>
>>>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
>> For additional commands, e-mail: ojb-user-help@db.apache.org
>>
>>
> 

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Re: PB behavor of Collection item delete ?

Posted by Armin Waibel <ar...@apache.org>.
ABOU LINA wrote:
> i think the coste of using ODMG is very big only looking  how in ODMG we
> query an object. in ODMG it use OQL (like SQL synthaxis where ....) so is
> very diferent to PB wiche use Criteria  to build a condition !!!!!
>
> what do you think Mr Armine
>

As said in my other post, it's possible to use the PB-api (with Criteria 
based queries) within ODMG and additionally you can tweak the odmg 
implementation:
- Disable implicit locking (lock all objects before modify them by hand)
- Disable pessimistic (object) locking and use optimistic locking for 
critical objects
http://db.apache.org/ojb/docu/guides/lockmanager.html

regards,
Armin

> On 3/9/06, ABOU LINA <am...@gmail.com> wrote:
>> Hi,
>>
>> ok so, i made DAO implementation with OJB PB in a critical project  and
>> we are in step of delivring some module of the application (the mainly
>> module now are developped and tested). my question is :
>>
>> 1. what will be the cost of migrating from PB to ODMG. ???
>> 2. there are some tools making  this  migration easy and fast ???
>> 3. in your opinion, the probleme about deleting collection elements
>> justify using ODMG instead of PB ???
>> 4. Best practice of ODMG and good examples ??
>>
>>
>> Thanks.
>>
>>
>>
>> On 3/9/06, Armin Waibel <ar...@apache.org> wrote:
>>> Hi,
>>>
>>> ABOU LINA wrote:
>>>> thank first,
>>>>
>>>> PersistenceBroker *delete elements* from the database that have been
>>> removed
>>>> from the collection only if i do this :
>>>> for example : A 1:n B
>>>> 1. i get A from database using OJB Broker.
>>>> 2. i delete one element B from A : A.getBCollection().remove(o);
>>>>
>>>> in this case yes the PB delete the element from database . but in
>>> generale
>>>> we don't
>>>> invoke remove but we construct a new collection and we set it :
>>>> 1. get A from database.
>>>> 2. Collection bCol = new ArrayList();
>>>>     A.setBCollection(bCol);
>>>>
>>>> in this case the element that not figure in bCol are not deleted
>>> because i
>>>> use ArrayList. (in my Application i can't put RemovalAwareList
>>> directly
>>>
>>> There is no need to handle with RemovalAwareList instances in your
>>> POJO's. Using type 'List' is sufficient and on insert of new objects you
>>>
>>> can use ArrayList, so
>>>
>>>> 2. Collection bCol = new ArrayList();
>>>>     A.setBCollection(bCol);
>>> is valid when insert new objects.
>>> But you are right, when updating objects you have to use
>>> Collection.remove (...) method.
>>>> 2. i delete one element B from A : A.getBCollection().remove(o);
>>> it's not allowed to replace the old List with a sub-List instance.
>>>
>>>
>>>> inorder to keep the application independent of OJB classes ...)
>>>>
>>>> so what is the solution please ... without using ODMG ?????
>>> There is none.
>>> That's the main difference between the PB-api and ODMG. The ODMG
>>> implementation use a "Unit of work" pattern (object state detection,
>>> detection of new/deleted objects) the PB-api does immediately write
>>> objects to DB and does not keep the objects state "in mind".
>>>
>>> For the next major release of OJB we plan to extend the PB-api to
>>> support a "unit of work" pattern with locking.
>>>
>>> regards,
>>> Armin
>>>
>>>> Thanks
>>>>
>>>> On 3/7/06, Armin Waibel <ar...@apache.org> wrote:
>>>>> Hi,
>>>>>
>>>>> ABOU LINA wrote:
>>>>>> Hi,
>>>>>> in ojb document :
>>>>>> ---------------------------------------
>>>>>> Say you use the PB to query an object O that has a collection
>>> attribute
>>>>> col
>>>>>> with five
>>>>>> elements a,b,c,d,e. Next you delete Objects d and e from col and
>>> store O
>>>>>> again with
>>>>>> PersistenceBroker.store(O);
>>>>>> PB will store the remaining objects a,b,c. But it will not delete d
>>> and
>>>>> e !
>>>>>> If you then
>>>>>> requery object O it will again contain a,b,c,d,e !!!
>>>>>> --------------------
>>>>>>
>>>>>> i ask if the new version of PB (1.0.4) still behave like this ???
>>>>> Oops! Seems you found some outdated documentation - I will fix this
>>> till
>>>>> next release.
>>>>> With corresponding settings OJB 1.0.4 is able to detect the deleted
>>>>> objects of the 1:n reference. More info see
>>>>>
>>>>>
>>> http://db.apache.org/ojb/docu/guides/basic-technique.html#1%3An+auto-xxx+setting
>>>>>
>>> http://db.apache.org/ojb/docu/guides/advanced-technique.html#which-collection-type
>>>>> regards,
>>>>> Armin
>>>>>
>>>>>
>>>>>
>>>>> ---------------------------------------------------------------------
>>>>> To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
>>>>> For additional commands, e-mail: ojb-user-help@db.apache.org
>>>>>
>>>>>
>>> ---------------------------------------------------------------------
>>> To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
>>> For additional commands, e-mail: ojb-user-help@db.apache.org
>>>
>>>
> 

---------------------------------------------------------------------
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Re: PB behavor of Collection item delete ?

Posted by ABOU LINA <am...@gmail.com>.
i think the coste of using ODMG is very big only looking  how in ODMG we
query an object. in ODMG it use OQL (like SQL synthaxis where ....) so is
very diferent to PB wiche use Criteria  to build a condition !!!!!

what do you think Mr Armine

On 3/9/06, ABOU LINA <am...@gmail.com> wrote:
>
> Hi,
>
> ok so, i made DAO implementation with OJB PB in a critical project  and
> we are in step of delivring some module of the application (the mainly
> module now are developped and tested). my question is :
>
> 1. what will be the cost of migrating from PB to ODMG. ???
> 2. there are some tools making  this  migration easy and fast ???
> 3. in your opinion, the probleme about deleting collection elements
> justify using ODMG instead of PB ???
> 4. Best practice of ODMG and good examples ??
>
>
> Thanks.
>
>
>
> On 3/9/06, Armin Waibel <ar...@apache.org> wrote:
> >
> > Hi,
> >
> > ABOU LINA wrote:
> > > thank first,
> > >
> > > PersistenceBroker *delete elements* from the database that have been
> > removed
> > > from the collection only if i do this :
> > > for example : A 1:n B
> > > 1. i get A from database using OJB Broker.
> > > 2. i delete one element B from A : A.getBCollection().remove(o);
> > >
> > > in this case yes the PB delete the element from database . but in
> > generale
> > > we don't
> > > invoke remove but we construct a new collection and we set it :
> > > 1. get A from database.
> > > 2. Collection bCol = new ArrayList();
> > >     A.setBCollection(bCol);
> > >
> > > in this case the element that not figure in bCol are not deleted
> > because i
> > > use ArrayList. (in my Application i can't put RemovalAwareList
> > directly
> >
> > There is no need to handle with RemovalAwareList instances in your
> > POJO's. Using type 'List' is sufficient and on insert of new objects you
> >
> > can use ArrayList, so
> >
> > > 2. Collection bCol = new ArrayList();
> > >     A.setBCollection(bCol);
> >
> > is valid when insert new objects.
> > But you are right, when updating objects you have to use
> > Collection.remove (...) method.
> > > 2. i delete one element B from A : A.getBCollection().remove(o);
> >
> > it's not allowed to replace the old List with a sub-List instance.
> >
> >
> > > inorder to keep the application independent of OJB classes ...)
> > >
> > > so what is the solution please ... without using ODMG ?????
> >
> > There is none.
> > That's the main difference between the PB-api and ODMG. The ODMG
> > implementation use a "Unit of work" pattern (object state detection,
> > detection of new/deleted objects) the PB-api does immediately write
> > objects to DB and does not keep the objects state "in mind".
> >
> > For the next major release of OJB we plan to extend the PB-api to
> > support a "unit of work" pattern with locking.
> >
> > regards,
> > Armin
> >
> > >
> > > Thanks
> > >
> > > On 3/7/06, Armin Waibel <ar...@apache.org> wrote:
> > >> Hi,
> > >>
> > >> ABOU LINA wrote:
> > >>> Hi,
> > >>> in ojb document :
> > >>> ---------------------------------------
> > >>> Say you use the PB to query an object O that has a collection
> > attribute
> > >> col
> > >>> with five
> > >>> elements a,b,c,d,e. Next you delete Objects d and e from col and
> > store O
> > >>> again with
> > >>> PersistenceBroker.store(O);
> > >>> PB will store the remaining objects a,b,c. But it will not delete d
> > and
> > >> e !
> > >>> If you then
> > >>> requery object O it will again contain a,b,c,d,e !!!
> > >>> --------------------
> > >>>
> > >>> i ask if the new version of PB (1.0.4) still behave like this ???
> > >> Oops! Seems you found some outdated documentation - I will fix this
> > till
> > >> next release.
> > >> With corresponding settings OJB 1.0.4 is able to detect the deleted
> > >> objects of the 1:n reference. More info see
> > >>
> > >>
> > http://db.apache.org/ojb/docu/guides/basic-technique.html#1%3An+auto-xxx+setting
> > >>
> > >>
> > http://db.apache.org/ojb/docu/guides/advanced-technique.html#which-collection-type
> > >>
> > >> regards,
> > >> Armin
> > >>
> > >>
> > >>
> > >> ---------------------------------------------------------------------
> > >> To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
> > >> For additional commands, e-mail: ojb-user-help@db.apache.org
> > >>
> > >>
> > >
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
> > For additional commands, e-mail: ojb-user-help@db.apache.org
> >
> >
>

Re: PB behavor of Collection item delete ?

Posted by ABOU LINA <am...@gmail.com>.
Hi,

ok so, i made DAO implementation with OJB PB in a critical project  and  we
are in step of delivring some module of the application (the mainly module
now are developped and tested). my question is :

1. what will be the cost of migrating from PB to ODMG. ???
2. there are some tools making  this  migration easy and fast ???
3. in your opinion, the probleme about deleting collection elements justify
using ODMG instead of PB ???
4. Best practice of ODMG and good examples ??


Thanks.


On 3/9/06, Armin Waibel <ar...@apache.org> wrote:
>
> Hi,
>
> ABOU LINA wrote:
> > thank first,
> >
> > PersistenceBroker *delete elements* from the database that have been
> removed
> > from the collection only if i do this :
> > for example : A 1:n B
> > 1. i get A from database using OJB Broker.
> > 2. i delete one element B from A : A.getBCollection().remove(o);
> >
> > in this case yes the PB delete the element from database . but in
> generale
> > we don't
> > invoke remove but we construct a new collection and we set it :
> > 1. get A from database.
> > 2. Collection bCol = new ArrayList();
> >     A.setBCollection(bCol);
> >
> > in this case the element that not figure in bCol are not deleted because
> i
> > use ArrayList. (in my Application i can't put RemovalAwareList directly
>
> There is no need to handle with RemovalAwareList instances in your
> POJO's. Using type 'List' is sufficient and on insert of new objects you
> can use ArrayList, so
>
> > 2. Collection bCol = new ArrayList();
> >     A.setBCollection(bCol);
>
> is valid when insert new objects.
> But you are right, when updating objects you have to use
> Collection.remove(...) method.
> > 2. i delete one element B from A : A.getBCollection().remove(o);
>
> it's not allowed to replace the old List with a sub-List instance.
>
>
> > inorder to keep the application independent of OJB classes ...)
> >
> > so what is the solution please ... without using ODMG ?????
>
> There is none.
> That's the main difference between the PB-api and ODMG. The ODMG
> implementation use a "Unit of work" pattern (object state detection,
> detection of new/deleted objects) the PB-api does immediately write
> objects to DB and does not keep the objects state "in mind".
>
> For the next major release of OJB we plan to extend the PB-api to
> support a "unit of work" pattern with locking.
>
> regards,
> Armin
>
> >
> > Thanks
> >
> > On 3/7/06, Armin Waibel <ar...@apache.org> wrote:
> >> Hi,
> >>
> >> ABOU LINA wrote:
> >>> Hi,
> >>> in ojb document :
> >>> ---------------------------------------
> >>> Say you use the PB to query an object O that has a collection
> attribute
> >> col
> >>> with five
> >>> elements a,b,c,d,e. Next you delete Objects d and e from col and store
> O
> >>> again with
> >>> PersistenceBroker.store(O);
> >>> PB will store the remaining objects a,b,c. But it will not delete d
> and
> >> e !
> >>> If you then
> >>> requery object O it will again contain a,b,c,d,e !!!
> >>> --------------------
> >>>
> >>> i ask if the new version of PB (1.0.4) still behave like this ???
> >> Oops! Seems you found some outdated documentation - I will fix this
> till
> >> next release.
> >> With corresponding settings OJB 1.0.4 is able to detect the deleted
> >> objects of the 1:n reference. More info see
> >>
> >>
> http://db.apache.org/ojb/docu/guides/basic-technique.html#1%3An+auto-xxx+setting
> >>
> >>
> http://db.apache.org/ojb/docu/guides/advanced-technique.html#which-collection-type
> >>
> >> regards,
> >> Armin
> >>
> >>
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
> >> For additional commands, e-mail: ojb-user-help@db.apache.org
> >>
> >>
> >
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
> For additional commands, e-mail: ojb-user-help@db.apache.org
>
>

Re: PB behavor of Collection item delete ?

Posted by Armin Waibel <ar...@apache.org>.
Hi,

ABOU LINA wrote:
> thank first,
> 
> PersistenceBroker *delete elements* from the database that have been removed
> from the collection only if i do this :
> for example : A 1:n B
> 1. i get A from database using OJB Broker.
> 2. i delete one element B from A : A.getBCollection().remove(o);
> 
> in this case yes the PB delete the element from database . but in generale
> we don't
> invoke remove but we construct a new collection and we set it :
> 1. get A from database.
> 2. Collection bCol = new ArrayList();
>     A.setBCollection(bCol);
> 
> in this case the element that not figure in bCol are not deleted because i
> use ArrayList. (in my Application i can't put RemovalAwareList directly

There is no need to handle with RemovalAwareList instances in your 
POJO's. Using type 'List' is sufficient and on insert of new objects you 
can use ArrayList, so

 > 2. Collection bCol = new ArrayList();
 >     A.setBCollection(bCol);

is valid when insert new objects.
But you are right, when updating objects you have to use 
Collection.remove(...) method.
 > 2. i delete one element B from A : A.getBCollection().remove(o);

it's not allowed to replace the old List with a sub-List instance.


> inorder to keep the application independent of OJB classes ...)
> 
> so what is the solution please ... without using ODMG ?????

There is none.
That's the main difference between the PB-api and ODMG. The ODMG 
implementation use a "Unit of work" pattern (object state detection, 
detection of new/deleted objects) the PB-api does immediately write 
objects to DB and does not keep the objects state "in mind".

For the next major release of OJB we plan to extend the PB-api to 
support a "unit of work" pattern with locking.

regards,
Armin

> 
> Thanks
> 
> On 3/7/06, Armin Waibel <ar...@apache.org> wrote:
>> Hi,
>>
>> ABOU LINA wrote:
>>> Hi,
>>> in ojb document :
>>> ---------------------------------------
>>> Say you use the PB to query an object O that has a collection attribute
>> col
>>> with five
>>> elements a,b,c,d,e. Next you delete Objects d and e from col and store O
>>> again with
>>> PersistenceBroker.store(O);
>>> PB will store the remaining objects a,b,c. But it will not delete d and
>> e !
>>> If you then
>>> requery object O it will again contain a,b,c,d,e !!!
>>> --------------------
>>>
>>> i ask if the new version of PB (1.0.4) still behave like this ???
>> Oops! Seems you found some outdated documentation - I will fix this till
>> next release.
>> With corresponding settings OJB 1.0.4 is able to detect the deleted
>> objects of the 1:n reference. More info see
>>
>> http://db.apache.org/ojb/docu/guides/basic-technique.html#1%3An+auto-xxx+setting
>>
>> http://db.apache.org/ojb/docu/guides/advanced-technique.html#which-collection-type
>>
>> regards,
>> Armin
>>
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
>> For additional commands, e-mail: ojb-user-help@db.apache.org
>>
>>
> 

---------------------------------------------------------------------
To unsubscribe, e-mail: ojb-user-unsubscribe@db.apache.org
For additional commands, e-mail: ojb-user-help@db.apache.org


Re: PB behavor of Collection item delete ?

Posted by ABOU LINA <am...@gmail.com>.
thank first,

PersistenceBroker *delete elements* from the database that have been removed
from the collection only if i do this :
for example : A 1:n B
1. i get A from database using OJB Broker.
2. i delete one element B from A : A.getBCollection().remove(o);

in this case yes the PB delete the element from database . but in generale
we don't
invoke remove but we construct a new collection and we set it :
1. get A from database.
2. Collection bCol = new ArrayList();
    A.setBCollection(bCol);

in this case the element that not figure in bCol are not deleted because i
use ArrayList. (in my Application i can't put RemovalAwareList directly
inorder to keep the application independent of OJB classes ...)

so what is the solution please ... without using ODMG ?????


Thanks

On 3/7/06, Armin Waibel <ar...@apache.org> wrote:
>
> Hi,
>
> ABOU LINA wrote:
> > Hi,
> > in ojb document :
> > ---------------------------------------
> > Say you use the PB to query an object O that has a collection attribute
> col
> > with five
> > elements a,b,c,d,e. Next you delete Objects d and e from col and store O
> > again with
> > PersistenceBroker.store(O);
> > PB will store the remaining objects a,b,c. But it will not delete d and
> e !
> > If you then
> > requery object O it will again contain a,b,c,d,e !!!
> > --------------------
> >
> > i ask if the new version of PB (1.0.4) still behave like this ???
>
> Oops! Seems you found some outdated documentation - I will fix this till
> next release.
> With corresponding settings OJB 1.0.4 is able to detect the deleted
> objects of the 1:n reference. More info see
>
> http://db.apache.org/ojb/docu/guides/basic-technique.html#1%3An+auto-xxx+setting
>
> http://db.apache.org/ojb/docu/guides/advanced-technique.html#which-collection-type
>
> regards,
> Armin
>
>
>
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>

Re: PB behavor of Collection item delete ?

Posted by Armin Waibel <ar...@apache.org>.
Hi,

ABOU LINA wrote:
> Hi,
> in ojb document :
> ---------------------------------------
> Say you use the PB to query an object O that has a collection attribute col
> with five
> elements a,b,c,d,e. Next you delete Objects d and e from col and store O
> again with
> PersistenceBroker.store(O);
> PB will store the remaining objects a,b,c. But it will not delete d and e !
> If you then
> requery object O it will again contain a,b,c,d,e !!!
> --------------------
> 
> i ask if the new version of PB (1.0.4) still behave like this ???

Oops! Seems you found some outdated documentation - I will fix this till 
next release.
With corresponding settings OJB 1.0.4 is able to detect the deleted 
objects of the 1:n reference. More info see
http://db.apache.org/ojb/docu/guides/basic-technique.html#1%3An+auto-xxx+setting
http://db.apache.org/ojb/docu/guides/advanced-technique.html#which-collection-type

regards,
Armin



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