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Hibernate version: \
3.1.3

Mapping documents:
<hibernate-mapping auto-import="false" default-access="com.pontis.platform.tgp.persistence.hibernate.PropertyBridge" default-cascade="none" default-lazy="true">
<class name="com.pontis.app.general.AppReference" table="APPREFERENCE" lazy="false" select-before-update="false" dynamic-update="false" dynamic-insert="false" discriminator-value="com.pontis.app.general.AppReference" >
<cache usage="read-write" />
<id type="java.lang.String" column="id" name="id">
<generator class="assigned" />
</id>
<discriminator type="string" force="false" insert="true"
column="my_discriminator" />
<version name="version" column="version"
type="java.lang.Integer"/>
.
.
.
</class>
<hibernate-mapping auto-import="false" default-cascade="none" default-lazy="true">
<subclass name="com.pontis.app.subscriber.SubscriberValue" extends="com.pontis.app.general.AppReference" lazy="false" select-before-update="false" discriminator-value="com.pontis.app.subscriber.SubscriberValue" />
</hibernate-mapping>


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

getHibernateTemplate().find("From com.pontis.app.subscriber.SubscriberValue
where refcode="123");
Full stack trace of any exception that occurs:

Name and version of the database you are using:

The generated SQL (show_sql=true):
Hibernate: select subscriber0_.id as id25_, subscriber0_.version as version25_, subscriber0_.lifeCycleState as lifeCycl4_25_, subscriber0_.creator as creator25_, subscriber0_.lastModifiedBy as lastModi6_25_, subscriber0_.availableFlag as availabl7_25_, subscriber0_.creationDate as creation8_25_, subscriber0_.lastModifiedDate as lastModi9_25_, subscriber0_.refCode as refCode25_, subscriber0_.refCodeDisplayString as refCode11_25_ from APPREFERENCE subscriber0_ where 1=2 and subscriber0_.refCode=?
Debug level Hibernate log excerpt:


I have a class, and a subclass. they are mapped onto the same table.
I am able to insert values of the sublcass through hibernate fine, but trying to perform a queryt on the subclass generates the above SQL that has a condition "where 1=2" - something that indicates that hiberate thinks it shouldn't return the results.

One more thing - the class (not subclass) extends a different class, which is not mapped at all.
so we have
SomeAbstractClass (not mapped)
|
AppReference(mapped as <class>)
|
SubscriberValue(mapped as <subclass>)


if I try to map the same classes using a table per subclass approach - all is well.

Any idea?

Assaf.

if I try and use spring's load (instead of find[=query]) on the instances of the subclass, it works fine -
meaning I can call load(SubscriberValue.class, "123"), and I get the instance.

but if I try the query "From com.pontis.app.subscriber.SubscriberValue
where refcode="123", the results are null and the SQL contains where 1=2.

Assaf.

Problem solved.

The mapped classes are actually interfaces.
I implemented an interceptor that takes care of the instantiation myself.

When hibernate mapps my classes (interfaces), it decides that they are abstract (since they are pojos+interfaces).

The interceptor is the part that actually makes sure that hibernate instantiates my objects, despite the fact that they are abstract.

When hibernate mapps the classes that belong to the per-hierarchy mapping,
it checks for abstract, and if the class is abstract, hibernate doesn't prepare the selects for them properly.

Basically, the solution was to tell hibernateabstract=false in the hbms.

Assaf.