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Posted to ojb-user@db.apache.org by ed...@mgrinformatica.com.br on 2004/03/28 19:52:15 UTC
Re:
MtoNCollectionPrefetcher.buildPrefetchCriteriaMultipleKeys(MtoNCollect
ionPrefetcher.java:338)
I think A way is more correct, besides more complex in some situations...
> hi edson,
>
> looks like my question wasn't clear enough ;) i know the join i have to do but
> i'm not sure about how to select the multiple keys when retrieving all A for
> several Cs:
>
> A)
>
> select *
> from A join B
> on A.A1 = B.A1 and A.A2 = B.A2
> join C
> on C.C1 = B.C1 and C.C2 = B.C2 and C.C3 = B.C3
> where
> (C.C1 = 1 and C2 = 2 and C.C3 = 3) or
> (C.C1 = 11 and C2 = 12 and C.C3 = 13) or
> (C.C1 = 21 and C2 = 22 and C.C3 = 23) or
> (C.C1 = 31 and C2 = 32 and C.C3 = 33)
>
> (C.C1 = and C2 = and C.C3 = ) will be repeated for every C.
> this will result in a quite complex sql depending on the number of Cs.
>
> an alternative would be to use IN-statement as in single-key :
>
> B)
>
> select *
> from A join B
> on A.A1 = B.A1 and A.A2 = B.A2
> join C
> on C.C1 = B.C1 and C.C2 = B.C2 and C.C3 = B.C3
> where
> C.C1 in ( 1, 11, 21, 31) and
> C.C2 in ( 2, 12, 22, 32) and
> C.C3 in ( 3, 13, 23, 33)
>
> the query is simpler but may return more As than necessary because the
> IN-statements do not constrain the combination of keys.
>
> i prefer alternative A) what do you think ?
>
> jakob
>
>
> Edson Carlos Ericksson Richter wrote:
>> Thinking less abstract, the field names of PK in A object are same field
>> names in B table, as the field names of PK in C are the same field names
>> in B.
>>
>> So, if A has the fields A1, A2 (PKs), and C has fields C1, C2, C3 (PKs),
>> then B has fields A1, A2, C1, C2, C3.
>>
>> So, the select will be:
>>
>> select *
>> from A join B
>> on A.A1 = B.A1 and A.A2 = B.A2
>> join C
>> on C.C1 = B.C1 and C.C2 = B.C2 and C.C3 = B.C3
>>
>> IMHO,
>>
>> the names of the fields are not important, but their position. The
>> "pointing-to-this-class" should be understood as 1st PK is pointing to
>> first field, and 2nd PK to the 2nd field.
>>
>> The first pointing-to-element should be mapped to 1st PK in the N
>> element, the 2nd to the second PK, and the 3rd, to 3rd PK.
>>
>> As far as I can see, the MtoN must know the CDS of the M element and the
>> N element, so the mapping could be done.
>>
>>
>> Richter
>>
>>
>> Edson Carlos Ericksson Richter wrote:
>>
>>> The expected result is something like
>>>
>>> A<->B<->C
>>>
>>> Where A is M side has PK with 2 fields, C is N side has PK with 3
>>> fields, B is indirection table, and has 5 fields.
>>>
>>> select *
>>> from A join B
>>> on A.field1 = B.field1 and A.field2 = B.field2
>>> join C
>>> on C.field1 = B.field3 and C.field2 = B.field4 and C.field3 = B.field5
>>>
>>> I expect this help.
>>>
>>>
>>> Edson Richter
>>>
>>>
>>> Jakob Braeuchi wrote:
>>>
>>>> hi edson,
>>>>
>>>> imo the whole handling of the multi-key criteria is a little bit weird.
>>>> what should the sql look like in your case ?
>>>>
>>>> jakob
>>>>
>>>> Edson Carlos Ericksson Richter wrote:
>>>>
>>>>> Hum... There is some instability here.
>>>>> I don't know what combination of dynamic proxies/collection proxies is
>>>>> causing this bug. I've fixed using either proxy=true in the collections
>>>>> inside each bean...
>>>>>
>>>>> Why? I really don't know. I'll need to compare each of the 12
>>>>> collections
>>>>> involved in this beans to know what's give the stack trace...
>>>>> I'll need sometime to restart the app 132 times to know :(
>>>>>
>>>>> Anyway, if someone could send me the rc5 implementation of the
>>>>> method, so I
>>>>> can compare with actual, I'll appreciate.
>>>>>
>>>>> Thanks in advantage.
>>>>>
>>>>>
>>>>> Edson Richter
>>>>>
>>>>>
>>>>> ----- Original Message ----- From: Edson Carlos Ericksson Richter
>>>>> To: 'OJB Users List'
>>>>> Sent: Wednesday, March 24, 2004 2:46 PM
>>>>> Subject:
>>>>> MtoNCollectionPrefetcher.buildPrefetchCriteriaMultipleKeys(MtoNCollectionPre
>>>>>
>>>>> fetcher.java:338)
>>>>>
>>>>>
>>>>> This bug is driving me crazy... Someone could point me what changed
>>>>> from rc5
>>>>> to 1.0 in this method (so I can at least fix locally)?
>>>>>
>>>>> The problem is a M:N mapping using composite pk pointing the M bean,
>>>>> and 1
>>>>> field pk pointing to the N bean.
>>>>> The stack trace is:
>>>>>
>>>>> java.lang.ArrayIndexOutOfBoundsException: 1
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.MtoNCollectionPrefetcher.buildPrefetchCrit
>>>>>
>>>>> eriaMultipleKeys(MtoNCollectionPrefetcher.java:338)
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.MtoNCollectionPrefetcher.buildPrefetchCrit
>>>>>
>>>>> eria(MtoNCollectionPrefetcher.java:259)
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.MtoNCollectionPrefetcher.buildPrefetchQuer
>>>>>
>>>>> y(MtoNCollectionPrefetcher.java:115)
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.CollectionPrefetcher.buildPrefetchQueries(
>>>>>
>>>>> CollectionPrefetcher.java:93)
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.MtoNCollectionPrefetcher.prefetchRelations
>>>>>
>>>>> hip(MtoNCollectionPrefetcher.java:68)
>>>>> at
>>>>> org.apache.ojb.broker.core.QueryReferenceBroker.performRetrievalTasks(QueryR
>>>>>
>>>>> eferenceBroker.java:277)
>>>>> at
>>>>> org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(QueryRe
>>>>>
>>>>> ferenceBroker.java:146)
>>>>> at
>>>>> org.apache.ojb.broker.core.QueryReferenceBroker.getCollectionByQuery(QueryRe
>>>>>
>>>>> ferenceBroker.java:203)
>>>>> at
>>>>> org.apache.ojb.broker.core.PersistenceBrokerImpl.getCollectionByQuery(Persis
>>>>>
>>>>> tenceBrokerImpl.java:1046)
>>>>> at
>>>>> org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(
>>>>>
>>>>> DelegatingPersistenceBroker.java:321)
>>>>> at
>>>>> org.apache.ojb.broker.core.DelegatingPersistenceBroker.getCollectionByQuery(
>>>>>
>>>>> DelegatingPersistenceBroker.java:321)
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.CollectionProxy.loadData(CollectionProxy.j
>>>>>
>>>>> ava:109)
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.ListProxy.loadData(ListProxy.java:148)
>>>>>
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.CollectionProxy.getData(CollectionProxy.ja
>>>>>
>>>>> va:362)
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.ListProxy.getListData(ListProxy.java:140)
>>>>>
>>>>> at
>>>>> org.apache.ojb.broker.accesslayer.ListProxy.get(ListProxy.java:71)
>>>>> at
>>>>> br.com.mgr.dialogs.ListBasedListModel.getElementAt(ListBasedListModel.java:6
>>>>>
>>>>> 3)
>>>>> at
>>>>> javax.swing.plaf.basic.BasicListUI.updateLayoutState(BasicListUI.java:1147)
>>>>>
>>>>> at
>>>>> javax.swing.plaf.basic.BasicListUI.maybeUpdateLayoutState(BasicListUI.java:1
>>>>>
>>>>> 098)
>>>>> at
>>>>> javax.swing.plaf.basic.BasicListUI.getPreferredSize(BasicListUI.java:281)
>>>>>
>>>>> at
>>>>> javax.swing.JComponent.getPreferredSize(JComponent.java:1275)
>>>>> at
>>>>> javax.swing.JList.getPreferredScrollableViewportSize(JList.java:1913)
>>>>> at
>>>>> javax.swing.ViewportLayout.preferredLayoutSize(ViewportLayout.java:72)
>>>>> at java.awt.Container.preferredSize(Container.java:1178)
>>>>> at java.awt.Container.getPreferredSize(Container.java:1162)
>>>>> at
>>>>> javax.swing.JComponent.getPreferredSize(JComponent.java:1277)
>>>>> at
>>>>> javax.swing.ScrollPaneLayout.preferredLayoutSize(ScrollPaneLayout.java:475)
>>>>>
>>>>> at java.awt.Container.preferredSize(Container.java:1178)
>>>>> at java.awt.Container.getPreferredSize(Container.java:1162)
>>>>> at
>>>>> javax.swing.JComponent.getPreferredSize(JComponent.java:1277)
>>>>> at
>>>>> java.awt.BorderLayout.preferredLayoutSize(BorderLayout.java:572)
>>>>> at java.awt.Container.preferredSize(Container.java:1178)
>>>>> at java.awt.Container.getPreferredSize(Container.java:1162)
>>>>> at
>>>>> javax.swing.JComponent.getPreferredSize(JComponent.java:1277)
>>>>> at
>>>>> javax.swing.plaf.basic.BasicTabbedPaneUI$TabbedPaneLayout.calculateSize(Basi
>>>>>
>>>>> cTabbedPaneUI.java:2001)
>>>>> at
>>>>> javax.swing.plaf.basic.BasicTabbedPaneUI$TabbedPaneLayout.preferredLayoutSiz
>>>>>
>>>>> e(BasicTabbedPaneUI.java:1975)
>>>>> at java.awt.Container.preferredSize(Container.java:1178)
>>>>> at java.awt.Container.getPreferredSize(Container.java:1162)
>>>>> at
>>>>> javax.swing.JComponent.getPreferredSize(JComponent.java:1277)
>>>>> at java.awt.GridBagLayout.GetLayoutInfo(GridBagLayout.java:892)
>>>>> at java.awt.GridBagLayout.getLayoutInfo(GridBagLayout.java:806)
>>>>> at java.awt.GridBagLayout.ArrangeGrid(GridBagLayout.java:1374)
>>>>> at java.awt.GridBagLayout.arrangeGrid(GridBagLayout.java:1337)
>>>>> at
>>>>> java.awt.GridBagLayout.layoutContainer(GridBagLayout.java:706)
>>>>> at java.awt.Container.layout(Container.java:1020)
>>>>> at java.awt.Container.doLayout(Container.java:1010)
>>>>> at java.awt.Container.validateTree(Container.java:1092)
>>>>> at java.awt.Container.validateTree(Container.java:1099)
>>>>> at java.awt.Container.validateTree(Container.java:1099)
>>>>> at java.awt.Container.validateTree(Container.java:1099)
>>>>> at java.awt.Container.validate(Container.java:1067)
>>>>> at
>>>>> javax.swing.RepaintManager.validateInvalidComponents(RepaintManager.java:353
>>>>>
>>>>> )
>>>>> at
>>>>> javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQu
>>>>>
>>>>> eueUtilities.java:116)
>>>>> at
>>>>> java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:178)
>>>>> at java.awt.EventQueue.dispatchEvent(EventQueue.java:454)
>>>>> at
>>>>> java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.ja
>>>>>
>>>>> va:201)
>>>>> at
>>>>> java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java
>>>>>
>>>>> :151)
>>>>> at
>>>>> java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:145)
>>>>> at
>>>>> java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:137)
>>>>> at
>>>>> java.awt.EventDispatchThread.run(EventDispatchThread.java:100)
>>>>>
>>>>>
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Edson Richter
>>>>>
>>>>>
>>>>>
>>>>> ---
>>>>> Outgoing mail is certified Virus Free.
>>>>> Checked by AVG anti-virus system (http://www.grisoft.com).
>>>>> Version: 6.0.637 / Virus Database: 408 - Release Date: 20/3/2004
>>>>
>>>>
>>>>
>>>>
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>>>>
>>>>
>>>
>>>
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>>
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