jess singh [https://community.jboss.org/people/singhjess] created the discussion "Cannot insert null into table error while starting a process" To view the discussion, visit: https://community.jboss.org/message/746402#746402 -------------------------------------------------------------- Hi all , we are using JBPM 5.3 on Jboss 7.1 with Hibernate 4 and using JBoss's transaciton manager  and seam managed persistence context, when I try to start  a  process I get the following error   08:53:14,876 WARN [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (http-localhost-127.0.0.1-8080-1) SQL Error: 23502, SQLState: 23502 08:53:14,878 ERROR [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (http-localhost-127.0.0.1-8080-1) NULL not allowed for column "INSTANCEID"; SQL statement: insert into ProcessInstanceInfo (InstanceId, id, lastModificationDate, lastReadDate, processId, processInstanceByteArray, startDate, state, OPTLOCK) values (null, ?, ?, ?, ?, ?, ?, ?, ?) [23502-161] 08:53:14,888 ERROR [org.drools.persistence.SingleSessionCommandService] (http-localhost-127.0.0.1-8080-1) Could not commit session: : org.hibernate.exception.ConstraintViolationException * * *public* *void*startProcess() { *try**{* *KnowledgeBase kbase = +readKnowledgeBase+();* *TransactionManager manager = (TransactionManager)* *new InitialContext().lookup("java:jboss/TransactionManager"**);* *// create the entity manager factory and register it in the environment* *EntityManagerFactory emf = Persistence.+createEntityManagerFactory+(* *"main"**);* *Environment env = KnowledgeBaseFactory.+newEnvironment+();* *env.set( EnvironmentName.*++*ENTITY_MANAGER_FACTORY*++*, emf );* *//env.set( EnvironmentName.TRANSACTION, getUserTransaction());* *env.set(EnvironmentName.*++*GLOBALS*++*, new* *MapGlobalResolver());* *env.set(EnvironmentName.*++*APP_SCOPED_ENTITY_MANAGER*++*, entityManager**);* *env.set(EnvironmentName.*++*TRANSACTION_MANAGER*++*, manager);* *Map<String, Object> params =* *new**HashMap<String, Object>();* *// org.drools.persistence.info.WorkItemInfo wi;* *//org.jbpm.task.Comment comment;* *params.put(**"name", "Arthur"**);* *params.put(**"money"**, 1800);* *// create a new knowledge session that uses JPA to store the runtime state* *StatefulKnowledgeSession ksession = JPAKnowledgeService.+newStatefulKnowledgeSession+( kbase,* *null**, env );* *int**sessionId = ksession.getId();* *System.*++*out*++*.println(sessionId);* *// invoke methods on your method here* *ksession.startProcess(* *"process_1"**, params);* *ksession.dispose();* *}* *catch**( Throwable t ) {* *t.printStackTrace();* *}* Here is my persistence.xml   < persistence xmlns= ++" http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence"+ + -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/746402#746402] Start a new discussion in jBPM at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]