On Sat, 29 May 2004 00:17:15 +0200, Stefan Frank wrote:
>
>Hello everybody
>
>I got into trouble with Castor and PostgreSQL. I'm currently using Castor
>0.9.5.3 and PostgreSQL 7.4.2 with the pg74.213.jdbc3.jar JDBC-driver.
>
>I have several problems:
>
>Connection-Pooling:
>
>If my database.xml looks like this:
><---------------------------------------------------------------------->
><database name="dbsa" engine="postgresql">
> <data-source class-name="org.postgresql.jdbc2.optional.PoolingDataSource">
> <params server-name="localhost" database-name="dbsa"
> initial-connections="2" max-connections="10"
> user="dbsa" password="seminarverwaltung" />
> </data-source>
> <mapping href="res/dbsa-mapping.xml" />
></database>
><---------------------------------------------------------------------->
>I get errors like this:
><---------------------------------------------------------------------->
>Exception: org.exolab.castor.mapping.MappingException: Nested error:
>java.lang.NullPointerException
>org.exolab.castor.jdo.DatabaseNotFoundException: No configuration loaded for
>database dbsa -- use the JDO interface to load a configuration for this
>database
> at org.exolab.castor.jdo.JDO.getDatabase(JDO.java:601)
> at ch.fhz.hta.dbsa.server.db.ModifyBroker.<init>(ModifyBroker.java:54)
> at Test.<init>(Test.java:49)
> at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
> at
>sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
> at
>sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
> at java.lang.reflect.Constructor.newInstance(Constructor.java:274)
> at junit.framework.TestSuite.createTest(TestSuite.java:131)
> at junit.framework.TestSuite.addTestMethod(TestSuite.java:114)
> at junit.framework.TestSuite.<init>(TestSuite.java:75)
> at
>org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.getTest(RemoteTestRunner.java:349)
> at
>org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:387)
> at
>org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:294)
> at
>org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:182)
><---------------------------------------------------------------------->
>If I use instead the normal driver like this:
><---------------------------------------------------------------------->
><database name="dbsa" engine="postgresql">
> <driver url="jdbc:postgresql://localhost/dbsa"
>class-name="org.postgresql.Driver">
> <param name="user" value="dbsa" />
> <param name="password" value="seminarverwaltung" />
> </driver>
> <mapping href="res/dbsa-mapping.xml" />
></database>
><---------------------------------------------------------------------->
>everything works fine. I don't know wheter PostgreSQL 7.4 supports
>connection-pooling. I just read that version 7.2 should have support for it.
>Or must I use Poolman as a pooling manager?
>
>Well the next point is much more important. In the documentation is only
>written that database-locking works with Oracle and Sybase. But it is nowhere
>mentioned that it also works with PostgreSQL. But on the other hand in the
>JDO-FAQ it is written, that PostgreSQL supports the main functions of Castor.
Can you please point me the exact place of this, and I will amend the docs accordingly.
>Because we are developing a three tier client, we can't use caching. The cache
>is disabled and we are requesting every object direct from the database. As a
>consequence we must lock a record on the database as soon as we want to
>modify the desired object (the business-layer is distributed on different
>machines).
>
>I tried to load the object with access-mode (short)3.
>
>But then PostgreSQL complains:
><---------------------------------------------------------------------->
>May 28, 2004 11:47:31 PM org.exolab.castor.jdo.engine.SQLEngine load
>SEVERE: A fatal error occurred while loading
>ch.fhz.hta.dbsa.server.entities.Organization using SQL: SELECT
>"room"."room_id","organization"."address","organization"."city","organization"."contact_person_department","organization"."contact_person_first_n
ame","organization"."contact_person_last_name","organization"."contact_person_telefon_number","organization"."fax_number","organization"."nam
e","organization"."organization_size","organization"."short_name","organization"."telefon_number","organization"."zip_code","organization"."is_delet
ed","organization"."last_edited"
>FROM "organization" LEFT OUTER JOIN "room" ON
>"organization"."organization_id"="room"."organization_id" WHERE
>"organization"."organization_id"=? FOR UPDATE
>org.postgresql.util.PSQLException: ERROR: SELECT FOR UPDATE cannot be applied
>to the nullable side of an outer join
><---------------------------------------------------------------------->
>The problem is obviously, that the Organization-Object holds a collection of
>Rooms (a reference would also lead to the error). But as long as this
>collection is empty (or the reference is null), PostgreSQL complains about
>the nullable side of the outer join.
>
>Is there any solution available?
>
>And my last question is about lazy loading.
>I have the Room class with a relation (1:1) to the Organization class.
Well, actually you happen to have a 1:M relation here, correct ?
><---------------------------------------------------------------------->
>class Room {
> private Collection m_oOrganization;
>(...)
> public void setM_oOrganization (Collection organization) {}
> public Collection getM_oOrganization ()
>}
><---------------------------------------------------------------------->
>class Organization { (..) }
><---------------------------------------------------------------------->
><class name="Room" (...)>
> <map-to table="room" />
> <cache-type type="none" />
> <field name="m_oOrganization" type="Organization" lazy="true"
>collection="collection">
> <sql name="organization_id" />
^^^^^^^^^^^^^^^^^^^^^^^^
> </field>
>(...)
><---------------------------------------------------------------------->
>As soon as I call the create(Object)-method and pass a Room-object
>I receive following error:
><---------------------------------------------------------------------->
>org.exolab.castor.jdo.PersistenceException: Nested error:
>java.lang.NumberFormatException: For input string: "[]"
> at
>org.exolab.castor.persist.TransactionContext.create(TransactionContext.java:921)
> at org.exolab.castor.jdo.engine.DatabaseImpl.create(DatabaseImpl.java:363)
> at ch.fhz.hta.dbsa.server.db.ModifyBroker.createRoom(ModifyBroker.java:177)
><---------------------------------------------------------------------->
^
I think that the problem here is with the way the <sql> element is defined. In this
definition, you have to point to the 'many-key' portion of the primary key
of M_oOrganization (assuming that such a class exists). Iow,
<field name="m_oOrganization" type="Organization" lazy="true" collection="collection">
<sql name="organization_id" />
</field>
should change to
<field name="m_oOrganization" type="Organization" lazy="true" collection="collection">
<sql many-key="room_id" />
</field>
assuming that the table definition for M_oOrganization includes a column 'room_id'
that is part of the primary key.
>
>Regards,
>
>Stefan
>
>
>
>
>
>-----------------------------------------------------------
>If you wish to unsubscribe from this mailing, send mail to
>[EMAIL PROTECTED] with a subject of:
> unsubscribe castor-user
>
-----------------------------------------------------------
If you wish to unsubscribe from this mailing, send mail to
[EMAIL PROTECTED] with a subject of:
unsubscribe castor-user
