persist

Is there any way to get an entity ID before the persist/flush? I mean: $entity = new PointData(); $form = $this->createForm(new PointDataType(), $entity); If I try $entity->getId() at this point, it returns nothing. I can get it working by: $em->persist($entity); $em->flush(); (supposing $em = $this->getDoctrine()->getEntityManager(); ) How can I achieve this? If you want to know the ID of an entity before it's been persisted to the database, then you obviously can't use generated identifiers. You'll need to find some way to generate unique identifiers yourself (perhaps some kind of hash

I have two entity beans defined as follows (unrelated stuff removed): @Entity @Table(...) public class MasterItem implements java.io.Serializable { private Set<CriticalItems> criticalItemses = new HashSet<CriticalItems>(0); @OneToMany(fetch = FetchType.EAGER, mappedBy = "masterItem", orphanRemoval = true, cascade = {javax.persistence.CascadeType.DETACH}) @Cascade({CascadeType.SAVE_UPDATE, CascadeType.DELETE}) public Set<CriticalItems> getCriticalItemses() { return this.criticalItemses; } } CriticalItems is defined as follows: @Entity @Table(...) public class CriticalItems implements java.io

I have the following spark job, trying to keep everything in memory: val myOutRDD = myInRDD.flatMap { fp => val tuple2List: ListBuffer[(String, myClass)] = ListBuffer() : tuple2List }.persist(StorageLevel.MEMORY_ONLY).reduceByKey { (p1, p2) => myMergeFunction(p1,p2) }.persist(StorageLevel.MEMORY_ONLY) However, when I looked in to the job tracker, I still have a lot of Shuffle Write and Shuffle spill to disk ... Total task time across all tasks: 49.1 h Input Size / Records: 21.6 GB / 102123058 Shuffle write: 532.9 GB / 182440290 Shuffle spill (memory): 370.7 GB Shuffle spill (disk): 15.4 GB

So far, my preference has been to always use EntityManager's merge() take care of both insert and update. But I have also noticed that merge performs an additional select queries before update/insert to ensure record does not already exists in the database. Now that I am working on a project requiring extensive (bulk) inserts to the database. From a performance point of view does it make sense to use persist instead of merge in a scenario where I absolutely know that I am always creating a new instance of objects to be persisted? Óscar López It's not a good idea using merge when a persist