this is my deletereg_code function . in that it cannot commit the transaction. Actually it works perfectly, but now it is not working. the code is:

public void deleteRegistrationMasterEntry(String reg_code) {
Session hibernateSession = HibernateUtil.currentSession();
Transaction transaction = HibernateUtil.beginTransaction();
transaction.begin();
String szQuery = "from " + DBConstants.REGISTRATION_MASTER_TABLE + " where " + DBConstants.REGISTRATION_CODE + "=?";
RegistrationMaster oRegistrationMaster = (RegistrationMaster) hibernateSession.createQuery(szQuery).setString(0, reg_code).uniqueResult();
moLogger.debug("REgistration code recieved"+reg_code);
if (oRegistrationMaster == null)
{
moLogger.debug("Null result after query");
}
else
{
moLogger.debug("Query returned success");
}
moLogger.debug("before delete reg.code");
hibernateSession.delete(oRegistrationMaster);
moLogger.debug("after delete reg.code");
moLogger.debug("before commiting transaction");
HibernateUtil.commitTransaction(transaction);
moLogger.debug("after completing transaction");
}

plz rely me asap

the Exception is

DEBUG 20-07-10 17:56:11,012 (processSMS,deleteRegistrationMasterEntry)[http-8080
-1]- Query : from RegistrationMaster where registrationCode=?
DEBUG 20-07-10 17:56:11,028 (processSMS,deleteRegistrationMasterEntry)[http-8080
-1]- REgistration code recieved33414868748148
DEBUG 20-07-10 17:56:11,028 (processSMS,deleteRegistrationMasterEntry)[http-8080
-1]- Query returned success
DEBUG 20-07-10 17:56:11,028 (processSMS,deleteRegistrationMasterEntry)[http-8080
-1]- before delete reg.code
DEBUG 20-07-10 17:56:11,028 (processSMS,deleteRegistrationMasterEntry)[http-8080
-1]- after delete reg.code
DEBUG 20-07-10 17:56:11,028 (processSMS,deleteRegistrationMasterEntry)[http-8080
-1]- before commiting transaction
ERROR 20-07-10 17:56:11,059 (processSMS,RegistrationCheck)[http-8080-1]- Excepti
on ossured while registration ....Rolling back all DB actions
org.hibernate.exception.ConstraintViolationException: Could not execute JDBC bat
ch update
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.j
ava:71)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelp
er.java:43)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:
253)
at org.hibernate.jdbc.AbstractBatcher.prepareStatement(AbstractBatcher.j
ava:92)
at org.hibernate.jdbc.AbstractBatcher.prepareStatement(AbstractBatcher.j
ava:87)
at org.hibernate.jdbc.AbstractBatcher.prepareBatchStatement(AbstractBatc
her.java:222)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(Abstrac
tEntityPersister.java:2224)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(Abstrac
tEntityPersister.java:2660)
at org.hibernate.action.EntityInsertAction.execute(EntityInsertAction.ja
va:56)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:250)
at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:234)

at org.hibernate.engine.ActionQueue.executeActions(ActionQueue.java:141)

at org.hibernate.event.def.AbstractFlushingEventListener.performExecutio
ns(AbstractFlushingEventListener.java:298)
at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlus
hEventListener.java:27)
at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1000)
at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:338)
at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java
:106)
at com.ss.trap.business.utility.HibernateUtil.commitTransaction(Hibernat
eUtil.java:96)
at com.ss.trap.managers.UserManager.deleteRegistrationMasterEntry(UserMa
nager.java:316)
at com.ss.trap.managers.UserManager.RegistrationCheck(UserManager.java:9
8)
at com.ss.trap.servlets.processSMS.registrationCommand(processSMS.java:5
15)
at com.ss.trap.servlets.processSMS.processRequest(processSMS.java:217)
at com.ss.trap.servlets.processSMS.doGet(processSMS.java:273)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Appl
icationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationF
ilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperV
alve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextV
alve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.j
ava:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.j
ava:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineVal
ve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.jav
a:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java
:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.proce
ss(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:44
7)
at java.lang.Thread.run(Thread.java:619)
Caused by: java.sql.BatchUpdateException: Batch entry 0 insert into public.user_
details (first_name, last_name, address, state, city, country, postalpin, altern
ate_number, alternate_number1, web_password, email, hotkey, pin, is_deleted, rol
e_id, user_id) values (NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NUL
L, NULL, 12345, abcd, 0, NULL, 1) was aborted. Call getNextException to see the
cause.
at org.postgresql.jdbc2.AbstractJdbc2Statement$BatchResultHandler.handle
Error(AbstractJdbc2Statement.java:2530)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutor
Impl.java:1317)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.ja
va:350)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeBatch(AbstractJdbc
2Statement.java:2592)
at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.jav
a:48)
at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:
246)
... 34 more