Feki Ahmed [https://community.jboss.org/people/bardelman] created the discussion "an org.hibernate.exception.ConstraintViolationException while persisting process instances" To view the discussion, visit: https://community.jboss.org/message/784931#784931 -------------------------------------------------------------- Hi, i m developping a web application based on https://community.jboss.org/people/bpmn2user/blog/2011/09/21/jbpm5-web-ex... this example. In order to make my application storing already-started/unfinished processes/sessions and being able to retrieve them later(which is an avantage of the jbpm framework..); i want that these processes to be persisted on the database and not to be erased and replaced by a new data when a new record is persisted ,so , it is clear that the problem is about the property "hibernate.hbm2ddl.auto" on the persistance.xml's persistance-unit configuration..  but i actually have a problem to do this. My persistance.xml  looks like this : <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <persistence version="1.0" xsi:schemaLocation=" http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd http://java.sun.com/xml/ns/persistence/orm http://java.sun.com/xml/ns/persistence/orm http://java.sun.com/xml/ns/persistence/orm_1_0.xsd http://java.sun.com/xml/ns/persistence/orm_1_0.xsd" xmlns:orm=" http://java.sun.com/xml/ns/persistence/orm http://java.sun.com/xml/ns/persistence/orm" xmlns:xsi=" http://www.w3.org/2001/XMLSchema-instance http://www.w3.org/2001/XMLSchema-instance" xmlns=" http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence">      <persistence-unit name="org.jbpm.persistence.jpa" transaction-type="JTA">         <provider>org.hibernate.ejb.HibernatePersistence</provider>         <jta-data-source>java:comp/env/jdbc/testDS1</jta-data-source>         <class>org.drools.persistence.info.SessionInfo</class>         <class>org.jbpm.persistence.processinstance.ProcessInstanceInfo</class>         <class>org.jbpm.persistence.processinstance.ProcessInstanceEventInfo</class>         <class>org.drools.persistence.info.WorkItemInfo</class>         <class>org.jbpm.process.audit.ProcessInstanceLog</class>         <class>org.jbpm.process.audit.NodeInstanceLog</class>         <class>org.jbpm.process.audit.VariableInstanceLog</class>               <class>org.jbpm.task.Task</class>                          <class>org.jbpm.task.Comment</class>                          <class>org.jbpm.task.Attachment</class>                          <class>org.jbpm.task.I18NText</class>                          <class>org.jbpm.task.SubTasksStrategy</class>                          <class>org.jbpm.task.Deadline</class>                          <class>org.jbpm.task.Escalation</class>                          <class>org.jbpm.task.Reassignment</class>                          <class>org.jbpm.task.Notification</class>                          <class>org.jbpm.task.BooleanExpression</class>                          <class>org.jbpm.task.User</class>                          <class>org.jbpm.task.PeopleAssignments</class>         <properties>              <!-- mysql dialect -->             <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>             <property name="hibernate.connection.autocommit" value="false"/>             <property name="hibernate.max_fetch_depth" value="3"/>             <property name="hibernate.hbm2ddl.auto" value="update" />             <property name="hibernate.show_sql" value="false" />             <property name="hibernate.transaction.manager_lookup_class" value="org.hibernate.transaction.BTMTransactionManagerLookup"/>         </properties>     </persistence-unit>     <persistence-unit name="org.jbpm.task">         <provider>org.hibernate.ejb.HibernatePersistence</provider>         <class>org.jbpm.task.Attachment</class>         <class>org.jbpm.task.Content</class>         <class>org.jbpm.task.BooleanExpression</class>         <class>org.jbpm.task.Comment</class>         <class>org.jbpm.task.Deadline</class>         <class>org.jbpm.task.Comment</class>         <class>org.jbpm.task.Deadline</class>         <class>org.jbpm.task.Delegation</class>         <class>org.jbpm.task.Escalation</class>         <class>org.jbpm.task.Group</class>         <class>org.jbpm.task.I18NText</class>         <class>org.jbpm.task.Notification</class>         <class>org.jbpm.task.EmailNotification</class>         <class>org.jbpm.task.EmailNotificationHeader</class>         <class>org.jbpm.task.PeopleAssignments</class>         <class>org.jbpm.task.Reassignment</class>         <class>org.jbpm.task.Status</class>         <class>org.jbpm.task.Task</class>         <class>org.jbpm.task.TaskData</class>         <class>org.jbpm.task.SubTasksStrategy</class>         <class>org.jbpm.task.OnParentAbortAllSubTasksEndStrategy</class>         <class>org.jbpm.task.OnAllSubTasksEndParentEndStrategy</class>         <class>org.jbpm.task.User</class>         <class>org.drools.persistence.info.SessionInfo</class>         <class>org.jbpm.persistence.processinstance.ProcessInstanceInfo</class>         <class>org.jbpm.persistence.processinstance.ProcessInstanceEventInfo</class>         <class>org.drools.persistence.info.WorkItemInfo</class>            <properties>                                                            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>             <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>             <property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/jbpm5webexpl" />             <property name="hibernate.connection.username" value="root"/>             <property name="hibernate.connection.password" value="sdfsdf"/>             <property name="hibernate.connection.autocommit" value="false" />             <property name="hibernate.max_fetch_depth" value="3"/>             <property name="hibernate.hbm2ddl.auto" value="update" />             <property name="hibernate.show_sql" value="false" />         </properties>     </persistence-unit> </persistence> while initiating a servlet which is responsible for the starting of the human-task service, users must be added : public class HumanTaskStartupServlet extends HttpServlet {            private static Log log = LogFactory.getLog(HumanTaskStartupServlet.class);            public void init() throws ServletException {                   super.init();                                     try {                               EntityManagerFactory emfTask = Persistence.createEntityManagerFactory( "org.jbpm.task" );                               TaskService taskService = new TaskService(emfTask, SystemEventListenerFactory.getSystemEventListener());           /*                    * Add the required users                    */                   TaskServiceSession taskSession = taskService.createSession();                     try {                           taskSession.addUser(new User("Administrator"));                           taskSession.addUser(new User("krisv"));                           taskSession.addUser(new User("john"));                           taskSession.addUser(new User("mary"));                                          } catch (Exception e) {                                                        e.printStackTrace();                  }                   /* Start Mina server for HT*/                   MinaTaskServer server = new MinaTaskServer(taskService);                   Thread thread = new Thread(server);                   thread.start();                   log.debug("Mina Server started ...");                               } catch (Throwable t) {                                         log.error(t.getMessage(), t.getCause());                                         throw new RuntimeException("can't start Mina server",t);                               }            } At the beginning, the property "hibernate.hbm2ddl.auto"was set to "create" so always only one record remain on the database when i changed it to "update" i got this ERROR : org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update           at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:94)           at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)           at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:275)           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:321)           at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:50)           at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1027)           at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:365)           at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:137)           at org.hibernate.ejb.TransactionImpl.commit(TransactionImpl.java:54)           at org.jbpm.task.service.TaskServiceSession.doOperationInTransaction(TaskServiceSession.java:716)           at org.jbpm.task.service.TaskServiceSession.persistInTransaction(TaskServiceSession.java:682)           at org.jbpm.task.service.TaskServiceSession.addUser(TaskServiceSession.java:69)           at com.sample.taskserver.HumanTaskStartupServlet.init(HumanTaskStartupServlet.java:73)           at javax.servlet.GenericServlet.init(GenericServlet.java:160)           at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1266)           at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1185)           at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1080)           at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5027)           at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5314)           at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)           at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)           at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)           at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:618)           at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:963)           at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1600)           at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)           at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)           at java.util.concurrent.FutureTask.run(Unknown Source)           at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)           at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)           at java.lang.Thread.run(Unknown Source) Caused by: java.sql.BatchUpdateException: Duplicate entry 'Administrator' for key 'PRIMARY'           at com.mysql.jdbc.PreparedStatement.executeBatchSerially(PreparedStatement.java:2020)           at com.mysql.jdbc.PreparedStatement.executeBatch(PreparedStatement.java:1451)           at org.hibernate.jdbc.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:70)           at org.hibernate.jdbc.AbstractBatcher.executeBatch(AbstractBatcher.java:268)           ... 30 more and unfortunatelly it should be a fatal error as the application coudn't continue : i also got this ERROR: 2012-12-26 01:45:33,559 (TaskProcessServlet.java:81) ERROR com.sample.processserver.TaskProcessServlet - Could not connect task client i need your help for this issue, CHEERS ! -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/784931#784931] Start a new discussion in jBPM Development at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]