About collection

21-30 of 200Refresh
Forum
30

collection of embedded objects

1. In general, are there any restrictions of the use of @Embedded objects in collections, compared to @Entity? 2. If you have a large nested collection of @Embedded objects, and you remove the parent @Entity, does the remove cascade through the whole collection? 3. Is searching through collections
Forum
30

Custom collection types

Hi   In our project in few places there are used collections from emf framework eg EcoreEMap http ... , nevertheless it causes some questions. I checked that i can easily change the type of collection between ... of this classes but only their content so I suppose that you treat collections some how differently. Can i
Forum
29

Lazy Init / Eager / Join Fetch collection strategy ? What to choose ?

Hello, I'm doing some tests to choose the best collection fetch strategy. I have entities with many lazy collections and i don't want to load them all. (depends on context) In JPA / Hibernate world ... seems to be more efficient than only fetch required collections. Can you confirm my observations ? To finish, wake
Forum
29

PersistenceManager.getObjectsById(Collection,boolean) throwing JDOException

I have a call to getObjectsById(Collection,boolean) that is throwing a JDOException the first time ... why this might occur? We're using ObjectDB 2.2.4_02. The collection being passed in is a HashSetcollection
Forum
29

No clue how to query with collection

getStreet();     int getStreetNo(); } @Entity class Contact {     Collection
collection with a concatenated value of street + streetNo (if not ... that selecting the first item of a collection ain't be a good idea. now I can select the right item
Forum
29

Fetching Collections Puzzle

(which is recommended anyway to improve performance). Paul,   As posted above your collection ... to go and retrive the first element of the collection. This will only work if you are within a transaction ... from Node n left outer join fetch n.children where ....." this will also fetch your collection
Forum
29

Nested Collection Query

if a particular member exist in one of the group? Nesting a collection directly in another collection, although supported by ObjectDB, is not valid in JPA. Accordingly the JPA query language does not ... . The recommended solution is avoid collections of collections, and instead wrap the internal collection in a user defined entity or embeddable class. snoopydoghk
Forum
29

PostUpdate collection null

Hello, I have an entity MyEntity with a collection attribute myCollection. I have an EntityListener ... , this collection is null. If I try to access the collection from the PreUpdate method, the collection is populated. The collection is eagerly fetched. public class MyEntity {     @OneToMany(fetch
Issue
29

Collection update does not increase entity version and is not persisted

Hello, I found a bug when adding elements to a collection of Entities: Event { Collection ... to a collection in an object of an old schema, in which the collection was not exist yet (as of changing ... Collection getAttachments() { if (attachments == null) attachments = new
Issue
29

JPQL support for mapped by (inverse) collections

As discussed and demonstrated in this forum thread, collection operators and methods (IS EMPTY, SIZE, MEMBER OF, IN) are currently not supported for mapped by (inverse) collections. These operations are supported for direct (not mapped by) collections. Navigation and JOIN is supported