docs: @Override
      public void clear() {
          EntityManager em = getEntityManager();
          Object newTx = joinTransaction(em);
          try {
              	        
  	        int deletedNodes = em.createQuery("delete FROM NodeInstanceLog WHERE processInstanceId in (select spl.processInstanceId FROM ProcessInstanceLog spl WHERE spl.status in (2, 3))").executeUpdate();
  	        logger.debug("CLEAR:: deleted node instances {}", deletedNodes);
  	        
  	        int deletedVariables = em.createQuery("delete FROM VariableInstanceLog WHERE processInstanceId in (select spl.processInstanceId FROM ProcessInstanceLog spl WHERE spl.status in (2, 3))").executeUpdate();
  	        logger.debug("CLEAR:: deleted variable instances {}", deletedVariables);
  	        
  	        int deletedProcesses = em.createQuery("delete FROM ProcessInstanceLog WHERE status in (2, 3)").executeUpdate();
              logger.debug("CLEAR:: deleted process instances {}", deletedProcesses);
          } finally {
          	closeEntityManager(em, newTx);
          }
      }