My DB Structure

STUDENT Table
CREATE TABLE MY_OWNER.STUDENT
(
STUDENT_ID VARCHAR2(50 BYTE),
STUDENT_FIRSTNAME VARCHAR2(50 BYTE),
STUDENT_LASTNAME VARCHAR2(50 BYTE)
);

ALTER TABLE MY_OWNER.STUDENT ADD ( CONSTRAINT STUDENT_PK PRIMARY KEY (STUDENT_ID));

STUDENT_ID is primary-key

EXAM Table
CREATE TABLE MY_OWNER.EXAM
(
EXAM_NAME VARCHAR2(50 BYTE),
STUDENT_ID VARCHAR2(50 BYTE),
EXAMMARKS NUMBER
);
ALTER TABLE MY_OWNER.EXAM ADD (CONSTRAINT EXAM_PK PRIMARY KEY (EXAM_NAME, STUDENT_ID));
ALTER TABLE MY_OWNER.EXAM ADD ( CONSTRAINT EXAM_R01 FOREIGN KEY (STUDENT_ID) REFERENCES MY_OWNER.STUDENT (STUDENT_ID));

STUDENT_ID & EXAM_NAME is composite primary-key
STUDENT_ID is foreign key reference to STUDENT_ID in student table

--------------
Foreign key in Exam table is part composite primary key
-- ------------
My Hibernate Mappings :

Student.hbm.xml
<?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="com.jagadeesh.hibernate.Student" table="STUDENT">
<id name="studentId" type="string">
<column name="STUDENT_ID" length="50" />
<generator class="uuid" />
</id>
<property name="studentFirstname" type="string">
<column name="STUDENT_FIRSTNAME" length="50" />
</property>
<property name="studentLastname" type="string">
<column name="STUDENT_LASTNAME" length="50" />
</property>
<set name="exams" inverse="true" lazy="false" table="EXAM" fetch="select" cascade="all-delete-orphan">
<key>
<column name="STUDENT_ID" length="50" not-null="true" />
</key>
<one-to-many class="com.jagadeesh.hibernate.Exam" />
</set>
</class>
</hibernate-mapping>

Exam.hbm.xml
<?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="com.jagadeesh.hibernate.Exam" table="EXAM">
<composite-id name="id" class="com.jagadeesh.hibernate.ExamId">
<key-property name="examName" type="string">
<column name="EXAM_NAME" length="50" />
</key-property>
<key-property name="studentId" type="string">
<column name="STUDENT_ID" length="50" />
</key-property>
</composite-id>
<many-to-one name="student" class="com.jagadeesh.hibernate.Student" update="false" insert="false" fetch="select">
<column name="STUDENT_ID" length="50" not-null="true" />
</many-to-one>
<property name="exammarks" type="big_decimal">
<column name="EXAMMARKS" precision="22" scale="0" />
</property>
</class>
</hibernate-mapping>

--------
It is able to create record in Student table with out cascade.(I need to create record Exam table also)

With cascade,

A per my understanding(from my R&D , and hibernate logs) Hibernate Try to
1) Create record in Student
2) Create record in Exam
3) Update Foreign-Key(Student_id) in Exam

Because Foreign-Key is part of primary key it is failing with ConstraintViolationException

Please correct my hibernate mapping, such a way
If I save Student with Exam data, It should create record in Both Student and Exam tables
(with out using join table)
---------------------------------------

Error Log

ERROR - Could not synchronize database state with session
org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:71)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:254)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:266)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:167)
at org.hibernate.event.def.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:298)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:27)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1001)
at com.wrightexpress.si.site.dao.SiteAdapterDao.save(SiteAdapterDao.java:390)
at com.jagadeesh.unittest.TestDaoTest.testSave(TestDaoTest.java:112)
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:597)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:73)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:46)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:180)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:41)
at org.junit.runners.ParentRunner$1.evaluate(ParentRunner.java:173)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
at org.junit.runners.ParentRunner.run(ParentRunner.java:220)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:45)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:460)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)
Caused by: java.sql.BatchUpdateException: ORA-01400: cannot insert NULL into ("WL_OWNER"."EXAM"."STUDENT_ID")

at oracle.jdbc.driver.DatabaseError.throwBatchUpdateException(DatabaseError.java:343)
at oracle.jdbc.driver.OraclePreparedStatement.executeBatch(OraclePreparedStatement.java:10698)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:48)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:247)
... 31 more
ERROR - HE-04
Error saving object: com.jagadeesh.hibernate.Student

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