one-to-one not deleted in db but in session-cache - bug?

curio · **Joined:** Tue Oct 05, 2004 9:45 am **Posts:** 263

Hibernate version: current cvs version

Mapping documents:
ClassA

Code:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 2.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd" >
    
<hibernate-mapping>
   <class name="ClassA" table="testClassA">
    
    <id name="idClassA"
        column="id"
        type="integer"
        unsaved-value="0">
      <generator class="increment"/>
    </id>
    
    <property name="dummy" column="dummy" type="string"/>
    
    <one-to-one
      name="classBRef"
      class="ClassB"
      outer-join="true"
      cascade="all"/>
  </class>
</hibernate-mapping>

ClassB

Code:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 2.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd" >
    
<hibernate-mapping>
   <class name="ClassB" table="testClassB">
    
    <id name="idClassB"
        column="id"
        type="integer"
        unsaved-value="0">
      <generator class="foreign">
         <param name="property">classARef</param>
      </generator>
    </id>
    
    <property name="dummy" column="dummy" type="string"/>
    
    <one-to-one
      name="classARef"
      class="ClassA"
      outer-join="true"
      constrained="true"/>
  </class>
</hibernate-mapping>

Code between sessionFactory.openSession() and session.close():

Code:

    Session s = super.createSession(new OtOInterceptor());
    Transaction t = s.beginTransaction();
    ClassA classA = (ClassA)s.load(ClassA.class, new Integer(1));
    boolean aHasB = classA.getClassBRef() != null;
    boolean bHasA = classA.getClassBRef().getClassARef() != null;
    System.err.println("--------[classA has classB?]--->"+aHasB);
    System.err.println("--------[classB has classA?]--->"+bHasA);

    // remove classB-Ref
    classA.getClassBRef().setClassARef(null);
    classA.setClassBRef(null);
    
    s.saveOrUpdate(classA);
    t.commit();
    
    classA = (ClassA)s.load(ClassA.class, new Integer(1));
    
    aHasB = classA.getClassBRef() != null;
    if (aHasB)
      bHasA = classA.getClassBRef().getClassARef() != null;
    else
      bHasA = false;
    System.err.println("--------[classA has classB?]--->"+aHasB);
    System.err.println("--------[classB has classA?]--->"+bHasA);
    
    
        
    s.close();

Full stack trace of any exception that occurs:
no exception ...

Name and version of the database you are using:IBM DB2/AS400

The generated SQL (show_sql=true):
please look at log-excerpt

Debug level Hibernate log excerpt:

Code:

[main] DEBUG net.sf.hibernate.transaction.JDBCTransaction  - begin
[main] DEBUG net.sf.hibernate.connection.DriverManagerConnectionProvider  - total checked-out connections: 0
[main] DEBUG net.sf.hibernate.connection.DriverManagerConnectionProvider  - using pooled JDBC connection, pool size: 0
[main] DEBUG net.sf.hibernate.transaction.JDBCTransaction  - current autocommit status:false
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - loading [ClassA#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - attempting to resolve [ClassA#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - object not resolved in any cache [ClassA#1]
[main] DEBUG net.sf.hibernate.persister.EntityPersister  - Materializing entity: [ClassA#1]
[main] DEBUG net.sf.hibernate.impl.BatcherImpl  - about to open: 0 open PreparedStatements, 0 open ResultSets
[main] DEBUG net.sf.hibernate.SQL  - select classa0_.id as id1_, classa0_.dummy as dummy1_, classb1_.id as id0_, classb1_.dummy as dummy0_ from DRKTEST.testClassA classa0_ left outer join DRKTEST.testClassB classb1_ on classa0_.id=classb1_.id where classa0_.id=?
[main] DEBUG net.sf.hibernate.impl.BatcherImpl  - preparing statement
[main] DEBUG net.sf.hibernate.type.IntegerType  - binding '1' to parameter: 1
[main] DEBUG net.sf.hibernate.loader.Loader  - processing result set
[main] DEBUG net.sf.hibernate.type.IntegerType  - returning '1' as column: id0_
[main] DEBUG net.sf.hibernate.loader.Loader  - result row: 1, 1
[main] DEBUG net.sf.hibernate.loader.Loader  - Initializing object from ResultSet: 1
[main] DEBUG net.sf.hibernate.loader.Loader  - Hydrating entity: ClassB#1
[main] DEBUG net.sf.hibernate.type.StringType  - returning 'classB - dummy' as column: dummy0_
[main] DEBUG net.sf.hibernate.loader.Loader  - Initializing object from ResultSet: 1
[main] DEBUG net.sf.hibernate.loader.Loader  - Hydrating entity: ClassA#1
[main] DEBUG net.sf.hibernate.type.StringType  - returning 'classA - dummy' as column: dummy1_
[main] DEBUG net.sf.hibernate.loader.Loader  - done processing result set (1 rows)
[main] DEBUG net.sf.hibernate.impl.BatcherImpl  - done closing: 0 open PreparedStatements, 0 open ResultSets
[main] DEBUG net.sf.hibernate.impl.BatcherImpl  - closing statement
[main] DEBUG net.sf.hibernate.loader.Loader  - total objects hydrated: 2
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - resolving associations for [ClassB#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - loading [ClassA#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - attempting to resolve [ClassA#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - resolved object in session cache [ClassA#1]
loading: ClassB@1e4853f
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - done materializing entity [ClassB#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - resolving associations for [ClassA#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - loading [ClassB#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - attempting to resolve [ClassB#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - resolved object in session cache [ClassB#1]
loading: ClassA@2bd3a
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - done materializing entity [ClassA#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - initializing non-lazy collections
--------[classA has classB?]--->true
--------[classB has classA?]--->true
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - saveOrUpdate() persistent instance
[main] DEBUG net.sf.hibernate.transaction.JDBCTransaction  - commit
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - flushing session
[main] DEBUG net.sf.hibernate.engine.Cascades  - processing cascades for: ClassA
[main] DEBUG net.sf.hibernate.engine.Cascades  - done processing cascades for: ClassA
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - Flushing entities and processing referenced collections
-------start[Interceptor: findDirty]--------
finding dirty for ClassB@1e4853f
[0] --- ClassB@1e4853f ----[dummy]: currentState=[classB - dummy]: previousState=[classB - dummy]----
[1] --- ClassB@1e4853f ----[classARef]: currentState=[null]: previousState=[ClassA@2bd3a]----
-------end[Interceptor: findDirty]--------
-------start[Interceptor: findDirty]--------
finding dirty for ClassA@2bd3a
[0] --- ClassA@2bd3a ----[dummy]: currentState=[classA - dummy]: previousState=[classA - dummy]----
[1] --- ClassA@2bd3a ----[classBRef]: currentState=[null]: previousState=[ClassB@1e4853f]----
-------end[Interceptor: findDirty]--------
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - Processing unreferenced collections
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - Scheduling collection removes/(re)creates/updates
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - Flushed: 0 insertions, 0 updates, 0 deletions to 2 objects
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - Flushed: 0 (re)creations, 0 updates, 0 removals to 0 collections
[main] DEBUG net.sf.hibernate.impl.Printer  - listing entities:
[main] DEBUG net.sf.hibernate.impl.Printer  - ClassB{classARef=null, dummy=classB - dummy, idClassB=1}
[main] DEBUG net.sf.hibernate.impl.Printer  - ClassA{idClassA=1, dummy=classA - dummy, classBRef=null}
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - executing flush
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - post flush
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - transaction completion
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - loading [ClassA#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - attempting to resolve [ClassA#1]
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - resolved object in session cache [ClassA#1]
--------[classA has classB?]--->false
--------[classB has classA?]--->false
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - closing session
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - disconnecting session
[main] DEBUG net.sf.hibernate.connection.DriverManagerConnectionProvider  - returning connection to pool, pool size: 1
[main] DEBUG net.sf.hibernate.impl.SessionImpl  - transaction completion

hi,

it seems to me, that there's a bug in handling the one-to-one relationship.
I've two classes with a simple one-to-one relationship and an Interceptor (only tracings, no changes).
Loading ClassA works perfectly and performing some changings will work perfectly, too.
The only thing that doesn't work as i thought it should work is setting the references on the 'foreign-side' to 'null'.
After calling 'saveOrUpdate' and 'commit' the references are 'null' as well as the 'currentstate' in the interceptor ... so everything looks fine for me ... but no delete-statement is executed ...

The first-level-session-cache is now in another state than the database ....
(as you can see in the log, after reloading classA from the session no reference to ClassB is available ...)

What am i doing wrong? Or is it a bug?

TIA
curio

curio · **Joined:** Tue Oct 05, 2004 9:45 am **Posts:** 263

sorry for reactivating this thread ...

is my question just stupid? :)
If i have a big mistake in it, a hint would be great .... i didn't menage to delete an object on the foreign-side of a one-to-one-relationship so far ... with 'one-to-many' everything works just fine ...

thx!
curio

emmanuel · **Posted:** Mon Nov 08, 2004 8:07 pm

Since it is a one-to-one it means the PK are the same. You cannot delete such assertion, unless you session.delete() one of the instances

curio · **Joined:** Tue Oct 05, 2004 9:45 am **Posts:** 263

hmmm ...

okay. then i will find a workaround ...

but couldn't it be possible (because hibernate 'knows' the old values and could detect that the foreign-side was set to 'null') that hibernate creates the delete-statement on it's own? Just as a wish :)

But thanks a lot for the answer! Then everything is okay (just a wish remains :) ) and i will try to handle it by hand ...

gtx
curio