Incomplete insert causes constraint violation (inheritance)

compsci101 · **Joined:** Thu Jul 06, 2006 3:06 am **Posts:** 6

Hi all :)

I'm having a problem with creating a new object that's defined in an inheritance hierarchy. The basic issue is that when the insert statement is generated for the base class, it's missing two properties that are foreign keys into other tables, causing a constraint violation. The insert statement for the derived class is not generated -- I'm not seeing it on the console, at the very least.

In any case, my object relationships are as follows:
1) A base class, TriviaGame, mapped into users_trivia_games. It references foreign keys in two other tables via the user and triviaGameType properties (also entities);

2) A derived class, SinglePlayerGame, mapped into users_single_player_trivia_games;

3) A User class, mapped into users -- a User has a collection of TriviaGames, and each TriviaGame knows who its User is;

4) A TriviaGameType class, mapped into trivia_game_types -- a TriviaGameType is assigned to each TriviaGame, and a TriviaGameType has a collection of games of its type;

The session factory initializes itself properly, and all other entities in my app work completely. An abridged (extraneous properties removed) version of the TriviaGame hierarchy is below.

Code:

<hibernate-mapping>
    <class name="TriviaGame" table="users_trivia_games" polymorphism="implicit">
        <id name="userTriviaGameId" type="int">
            <column name="user_trivia_game_id" />
            <generator class="native" />
        </id>
        <many-to-one name="user" column="user_id" not-null="true" class="User" insert="false" update="false"/>
        <many-to-one name="triviaGameType" column="trivia_game_type_id" not-null="true" class="TriviaGameType" insert="false" update="false"/>

        <property name="highestScore" type="int" column="highest_score" not-null="true"/>
        <property name="totalQuestions" type="int" column="total_questions" not-null="true"/>
        <property name="datePlayed" type="timestamp" column="date_played" not-null="true"/>
        
        <joined-subclass name="SinglePlayerGame" table="users_single_player_trivia_games">
             <key column="user_trivia_game_id"/>
           <property name="timeElapsed" type="int" column="time_elapsed"/>
        </joined-subclass>
        
    </class>
 </hibernate-mapping>

Similarly, the mapping for User and TriviaGameType follow:

Code:

<hibernate-mapping>
    <class name="User" table="users">
        <id name="userId" type="int">
            <column name="user_id" />
            <generator class="native" />
        </id>
   <set name="triviaGames" inverse="true" table="users_trivia_games">
      <key column="user_id" not-null="true" />
      <one-to-many class="TriviaGame" />
   </set>
</hibernate-mapping>

<hibernate-mapping>
    <class name="TriviaGameType" table="trivia_game_type">
        <id name="triviaGameTypeId" type="int">
            <column name="trivia_game_type_id" />
            <generator class="native" />
        </id>
        <set name="triviaGames" table="users_trivia_games">
            <key column="trivia_game_type_id" />
            <one-to-many class="TriviaGame" />
        </set>
    </class>
</hibernate-mapping>

Everything goes fine until I try to save the new game:

Code:

            Session hibernateSession = HibernateSessionFactory.getSession();
            Transaction tx = hibernateSession.beginTransaction();
            User user = (User)hibernateSession.getNamedQuery("userById").setInteger("userId", createGame.getPlayer().getId()).uniqueResult();
            TriviaGameType triviaGameType = (TriviaGameType)hibernateSession.getNamedQuery("singlePlayerGameType").uniqueResult();

            Set<TriviaGame> userTriviaGames = user.getTriviaGames();
            Set<TriviaGame> triviaGameTypeTriviaGames = triviaGameType.getTriviaGames(); 

            // Create a new TriviaGame entry for the User
            SinglePlayerGame game = new SinglePlayerGame(user, triviaGameType);
            game.setDatePlayed(new Date());
            
            userTriviaGames.add(game);
            triviaGameTypeTriviaGames.add(game);
            
            hibernateSession.save(game);

I see that the following insert statement is created, but nothing more:

Code:

Hibernate: insert into users_trivia_games (highest_score, total_questions, date_played) values (?, ?, ?)

I'm expecting to see "user_id" and "trivia_game_type_id" in the column list as well, as well as an insert into the users_single_player_trivia_games table. The foreign key constraint failure comes, again, from user_id not being provided.

I realize this is a lot of stuff, but I'm really stumped. I'd like to avoid removing the inheritance, and I'm not sure what I'm doing wrong as I have MANY other types mapped and working this exact same way.

Thanks in advance for any help.
C

corzar71 · **Joined:** Thu Jun 01, 2006 5:09 am **Posts:** 16

I had the same problem. I'm looking for a better solution, but a workaround is to "extract" ids as properties and setting them by code.
In your case:

add

<property name="userTriviaGameId" type="int" column="user_trivia_game_id" not-null="true"/>

and

<property name="userId" type="int" column="user_id" not-null="true"/>

Remeber to add them to java class and set them in the backbean.

Bye

PS
if i was useful please remeber to rate me

compsci101 · **Joined:** Thu Jul 06, 2006 3:06 am **Posts:** 6

That seems to do the trick!

I don't know why it works, and I'm past caring at this point.

Thanks very much!
C

frusso · **Posted:** Thu Jul 06, 2006 11:59 pm

In TriviaGame, you have the <many-to-one> to user mapped as insert="false", update="false". Then in User, you have the set of triviaGames mapped as inverse="true". So nobody ever tries to set the foreign key.

corzar71 · **Joined:** Thu Jun 01, 2006 5:09 am **Posts:** 16

I tried to set inverse="false" leaving the rest unchanged but it doesn't work.

frusso · **Posted:** Fri Jul 07, 2006 4:51 am

Could you post your mapping?

corzar71 · **Joined:** Thu Jun 01, 2006 5:09 am **Posts:** 16

I suppressed unuseful properties:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
<class name="unibiblio.dati.anagrafica.DAO.Persone" table="persone">
<composite-id name="id" class="unibiblio.dati.anagrafica.DAO.PersoneId">
<key-property name="idUtente" type="int">
<column name="id_utente" />
</key-property>
<key-property name="codbib" type="int">
<column name="codbib" />
</key-property>
</composite-id>
<many-to-one name="dizLingue" class="unibiblio.dati.anagrafica.DAO.DizLingue" fetch="select">
<column name="lingua" length="2" />
</many-to-one>
<many-to-one name="dizProfessioni" class="unibiblio.dati.anagrafica.DAO.DizProfessioni" update="false" insert="false" fetch="select">
<column name="lingua" length="2" />
<column name="codprofessione" length="2" not-null="true" />
</many-to-one>
</class>
</hibernate-mapping>

<hibernate-mapping>
<class name="unibiblio.dati.anagrafica.DAO.DizProfessioni" table="diz_professioni">
<composite-id name="id" class="unibiblio.dati.anagrafica.DAO.DizProfessioniId">
<key-property name="lingua" type="string">
<column name="lingua" length="2" />
</key-property>
<key-property name="codprofessione" type="string">
<column name="codprofessione" length="2" />
</key-property>
</composite-id>
<many-to-one name="dizLingue" class="unibiblio.dati.anagrafica.DAO.DizLingue" update="false" insert="false" fetch="select">
<column name="lingua" length="2" not-null="true" />
</many-to-one>
<property name="professione" type="string">
<column name="professione" length="50" />
</property>
<set name="persones" inverse="false">
<key>
<column name="lingua" length="2" />
<column name="codprofessione" length="2" not-null="true" />
</key>
<one-to-many class="unibiblio.dati.anagrafica.DAO.Persone" />
</set>
</class>
</hibernate-mapping>

compsci101 · **Joined:** Thu Jul 06, 2006 3:06 am **Posts:** 6

Just a quick note to let you guys know that removing the insert="false" and update="false" on any foreign key properties did indeed work for me. Thanks very much frusso.

The only thing that still didn't really make complete sense to me is that I had to include the many-to-one mapping to the user on both the base class and the derived class mapping. That is, there is a many-to-one mapping on both TriviaGame and SinglePlayerTriviaGame. user_id is on the users_single_player_trivia_games table, so I suppose this makes sense -- I just don't see why it wouldn't pick up the mapping from the base class (it's too much to expect it to work that out automatically, I suppose).

I'm now having a different problem with a null or transitive backref error on a class related to the TriviaGame hierarchy, but I think I'll look around a bit first and maybe start a new topic on that one.

Thanks again for all your help, guys.
C

compsci101 · **Joined:** Thu Jul 06, 2006 3:06 am **Posts:** 6

By the way, corzar71, I thought that one of the ends of a bidirectional association had to be marked as inverse -- specifically, the many-sided end -- to prevent the same entity from being inserted twice.

Is this just me reading the mapping docs incorrectly again?

frusso · **Posted:** Fri Jul 07, 2006 12:40 pm

From the docs, section 6.2.5:
Very important note: If the foreign key column of a <one-to-many> association is declared NOT NULL, you must declare the <key> mapping not-null="true" or use a bidirectional association with the collection mapping marked inverse="true". See the discussion of bidirectional associations later in this chapter.

And then in section 7.4.1:
It is important that you define not-null="true" on the <key> element of the collection mapping if the underlying foreign key column is NOT NULL. Don't only declare not-null="true" on a possible nested <column> element, but on the <key> element.

The mapping of the set DizProfessioni.persones declares the nested codprofessione column as not-null, but not the <key> itself. That may be the problem.

The other alternative is to declare the set as inverse="true", but remove update="false" insert="false" on the many-to-one side. For lists you need to let Hibernate manage the association from the collection side so it can maintain the index column, but for sets it should work fine to manage the association from the many-to-one side.

corzar71 · **Joined:** Thu Jun 01, 2006 5:09 am **Posts:** 16

I tried with not null="true" also in key property and it doesn't work.
I deleted <<insert="false" update="false">> but when stating it gave me this exception:

2:17:00,734 ERROR [STDERR] org.hibernate.MappingException: Repeated column in mapping for entity: unibiblio.dati.anagrafica.DAO.Persone column: lingua (should be mapped with insert="false" update="false")
at org.hibernate.mapping.PersistentClass.checkColumnDuplication(PersistentClass.java:575)
at org.hibernate.mapping.PersistentClass.checkPropertyColumnDuplication(PersistentClass.java:597)
at org.hibernate.mapping.PersistentClass.checkColumnDuplication(PersistentClass.java:615)
at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:405)
at org.hibernate.mapping.RootClass.validate(RootClass.java:192)
at org.hibernate.cfg.Configuration.validate(Configuration.java:988)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1173)
at org.jboss.seam.core.Hibernate.startup(Hibernate.java:53)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.seam.util.Reflections.invoke(Reflections.java:13)
at org.jboss.seam.util.Reflections.invokeAndWrap(Reflections.java:32)
at org.jboss.seam.Component.callComponentMethod(Component.java:1119)
at org.jboss.seam.Component.callCreateMethod(Component.java:1107)
at org.jboss.seam.Component.newInstance(Component.java:1096)
at org.jboss.seam.Component.getInstance(Component.java:1044)
at org.jboss.seam.Component.getInstance(Component.java:1027)
at org.jboss.seam.contexts.Lifecycle.startup(Lifecycle.java:88)
at org.jboss.seam.contexts.Lifecycle.endInitialization(Lifecycle.java:68)
at org.jboss.seam.init.Initialization.init(Initialization.java:94)
at org.jboss.seam.servlet.SeamListener.contextInitialized(SeamListener.java:30)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3729)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4183)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:759)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:739)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:524)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.commons.modeler.BaseModelMBean.invoke(BaseModelMBean.java:503)
at org.jboss.mx.server.RawDynamicInvoker.invoke(RawDynamicInvoker.java:164)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.apache.catalina.core.StandardContext.init(StandardContext.java:5107)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.commons.modeler.BaseModelMBean.invoke(BaseModelMBean.java:503)
at org.jboss.mx.server.RawDynamicInvoker.invoke(RawDynamicInvoker.java:164)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.web.tomcat.tc5.TomcatDeployer.performDeployInternal(TomcatDeployer.java:297)
at org.jboss.web.tomcat.tc5.TomcatDeployer.performDeploy(TomcatDeployer.java:103)
at org.jboss.web.AbstractWebDeployer.start(AbstractWebDeployer.java:371)
at org.jboss.web.WebModule.startModule(WebModule.java:83)
at org.jboss.web.WebModule.startService(WebModule.java:61)
at org.jboss.system.ServiceMBeanSupport.jbossInternalStart(ServiceMBeanSupport.java:289)
at org.jboss.system.ServiceMBeanSupport.jbossInternalLifecycle(ServiceMBeanSupport.java:245)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:260)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.system.ServiceController$ServiceProxy.invoke(ServiceController.java:978)
at $Proxy0.start(Unknown Source)
at org.jboss.system.ServiceController.start(ServiceController.java:417)
at sun.reflect.GeneratedMethodAccessor9.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:260)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanProxyExt.java:190)
at $Proxy29.start(Unknown Source)
at org.jboss.web.AbstractWebContainer.start(AbstractWebContainer.java:466)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.interceptor.AbstractInterceptor.invoke(AbstractInterceptor.java:133)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.interceptor.ModelMBeanOperationInterceptor.invoke(ModelMBeanOperationInterceptor.java:142)
at org.jboss.mx.interceptor.DynamicInterceptor.invoke(DynamicInterceptor.java:97)
at org.jboss.system.InterceptorServiceMBeanSupport.invokeNext(InterceptorServiceMBeanSupport.java:238)
at org.jboss.ws.server.WebServiceDeployer.start(WebServiceDeployer.java:117)
at org.jboss.deployment.SubDeployerInterceptorSupport$XMBeanInterceptor.start(SubDeployerInterceptorSupport.java:188)
at org.jboss.deployment.SubDeployerInterceptor.invoke(SubDeployerInterceptor.java:95)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:260)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanProxyExt.java:190)
at $Proxy30.start(Unknown Source)
at org.jboss.deployment.MainDeployer.start(MainDeployer.java:1007)
at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:808)
at org.jboss.deployment.MainDeployer.deploy(MainDeployer.java:771)
at sun.reflect.GeneratedMethodAccessor52.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.interceptor.AbstractInterceptor.invoke(AbstractInterceptor.java:133)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.interceptor.ModelMBeanOperationInterceptor.invoke(ModelMBeanOperationInterceptor.java:142)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:260)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanPro
12:17:00,734 ERROR [STDERR] xyExt.java:190)
at $Proxy8.deploy(Unknown Source)
at org.jboss.deployment.scanner.URLDeploymentScanner.deploy(URLDeploymentScanner.java:334)
at org.jboss.deployment.scanner.URLDeploymentScanner.scan(URLDeploymentScanner.java:504)
at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.doScan(AbstractDeploymentScanner.java:207)
at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.loop(AbstractDeploymentScanner.java:218)
at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.run(AbstractDeploymentScanner.java:197)

frusso · **Posted:** Wed Jul 12, 2006 1:32 pm

Yes, I just noticed in your mapping that Persone.dizLingue uses the lingua column as a foreign key to DizLingue, then again as one component of the composite foreign key to DizProfessioni. Assuming this is intentional, you do need to make sure that only one of these is actually maintaining the content of the lingua column. Basically, as many properties as you want can 'read' the contents of this column (via insert="false" update="false", or by using formula instead of column in the declaration), but only one can 'write' the column. In this case, my best guess is that you want Persone.dizProfessioni to be where things get set (i.e. insert="true" update="true"), and Persone.dizLingue to be read-only (insert="false" update="false").

corzar71 · **Joined:** Thu Jun 01, 2006 5:09 am **Posts:** 16

Yes, I thought that but I have another mapping (I didn't post it) that uses lingua as id, so I'll have the same problem. Below there's the complete mapping I use. Let's try to understand if there's a way to resolve it else I'll open a bug ticket to the hibernate developers space.

<hibernate-mapping>
<class name="unibiblio.dati.anagrafica.DAO.Persone" table="persone">
<composite-id name="id" class="unibiblio.dati.anagrafica.DAO.PersoneId">
<key-property name="idUtente" type="java.lang.Integer">
<column name="id_utente" />
</key-property>
<key-property name="codbib" type="java.lang.Integer">
<column name="codbib" />
</key-property>
</composite-id>
<many-to-one name="dizNazioni" class="unibiblio.dati.anagrafica.DAO.DizNazioni" fetch="select">
<column name="siglanazione" length="2" not-null="true" />
</many-to-one>
<many-to-one name="dizTitolidistudio" class="unibiblio.dati.anagrafica.DAO.DizTitolidistudio" update="false" insert="false" fetch="select">
<column name="lingua" length="2" />
<column name="codice_titolostudio" length="1" />
</many-to-one>
<many-to-one name="dizLingue" class="unibiblio.dati.anagrafica.DAO.DizLingue" fetch="select">
<column name="lingua" length="2" />
</many-to-one>
<many-to-one name="anagbiblio" class="unibiblio.dati.anagrafica.DAO.Anagbiblio" update="false" insert="false" fetch="select">
<column name="codbib" not-null="true" />
</many-to-one>
<many-to-one name="persone" class="unibiblio.dati.anagrafica.DAO.Persone" fetch="select">
<column name="id_padre" />
<column name="codbib_padre" />
</many-to-one>
<many-to-one name="dizProfessioni" class="unibiblio.dati.anagrafica.DAO.DizProfessioni" update="false" insert="false" fetch="select">
<column name="lingua" length="2" />
<column name="codprofessione" length="2" not-null="true" />
</many-to-one>
<many-to-one name="dizCategorieutenti" class="unibiblio.dati.anagrafica.DAO.DizCategorieutenti" fetch="select">
<column name="tip_ute" length="1" not-null="true" />
</many-to-one>
<many-to-one name="dizProvincie" class="unibiblio.dati.anagrafica.DAO.DizProvincie" fetch="select">
<column name="siglaprovincia" length="2" />
</many-to-one>
<property name="userName" type="string">
<column name="user_name" length="30" />
</property>
<property name="password" type="string">
<column name="password" length="30" />
</property>
.
.
.
.
.
.
</class>
</hibernate-mapping>

<hibernate-mapping>
<class name="unibiblio.dati.anagrafica.DAO.DizProfessioni" table="diz_professioni">
<composite-id name="id" class="unibiblio.dati.anagrafica.DAO.DizProfessioniId">
<key-property name="lingua" type="string">
<column name="lingua" length="2" />
</key-property>
<key-property name="codprofessione" type="string">
<column name="codprofessione" length="2" />
</key-property>
</composite-id>
<many-to-one name="dizLingue" class="unibiblio.dati.anagrafica.DAO.DizLingue" update="false" insert="false" fetch="select">
<column name="lingua" length="2" not-null="true" />
</many-to-one>
<property name="professione" type="string">
<column name="professione" length="50" />
</property>
<set name="persones" inverse="true">
<key>
<column name="lingua" length="2" />
<column name="codprofessione" length="2" not-null="true" />
</key>
<one-to-many class="unibiblio.dati.anagrafica.DAO.Persone" />
</set>
</class>
</hibernate-mapping>

<hibernate-mapping>
<class name="unibiblio.dati.anagrafica.DAO.DizTitolidistudio" table="diz_titolidistudio">
<composite-id name="id" class="unibiblio.dati.anagrafica.DAO.DizTitolidistudioId">
<key-property name="lingua" type="string">
<column name="lingua" length="2" />
</key-property>
<key-property name="codiceTitolostudio" type="string">
<column name="codice_titolostudio" length="1" />
</key-property>
</composite-id>
<many-to-one name="dizLingue" class="unibiblio.dati.anagrafica.DAO.DizLingue" update="false" insert="false" fetch="select">
<column name="lingua" length="2" not-null="true" />
</many-to-one>
<property name="titolo" type="string">
<column name="titolo" length="50" not-null="true" />
</property>
<set name="persones" inverse="true">
<key>
<column name="lingua" length="2" />
<column name="codice_titolostudio" length="1" />
</key>
<one-to-many class="unibiblio.dati.anagrafica.DAO.Persone" />
</set>
</class>
</hibernate-mapping>