About Data Set

forum_thread

Listing large number of complicated objects with paging.

Hi, For last few hours I was working on a problem with bad performance and memory problems with such a simple query: select prod from Product prod order by prod.id ASC Right now I have 55541 'Product' (attached to this post) entities in database and I'm trying to speed listing them with paging. The problem is, that running code that looks like this: ... DEBUG pl.hplxtool.dao.impl.ProductDAOImpl - Returning data Query manager builds plan like this: [2011-11-15 19:30:59 ... 21:27 OK, I just set lazy hint. Query plan is a little bit different in this case: ...

 
forum_thread

Efficient query on EmbeddedId

Hi! I have an entity class with an @EmbeddedId (field1 int and field2 int). Based on the manual, I understand that making a query just on entity.id.field1 is efficient. Of course, making a query containing the whole EmbeddedId is the ideal case, and I use it, but I need more use cases. ... to duplicate entity.id.field2 into entity.field2 and then set an index on it? I am really interested in this question. Thank you ... in an ordinary composite index, since a full scan of the data is required rather than just the index, which is smaller. In that ...

 
forum_thread

Query becomes slower on moving from ObjectDB 1.x to ObjectDB 2.x

Hi, I upgraded the odb file using converter.jar which is having 15943 entry. Previously, with object 1.x, the same query was getting executed within an seconds and now the same is taking around 40 seconds in object db 2.x I have build the query using the follwoing Query query = persistanceManager.newQuery("LogEntryAttrebuteImpl.calss", "typeIndexes.contains(this.type) && logEntryIdList.contains(this.logEntryId)"); ... ) ; List param1 has the following data [5] List param2 , data is attached in the file as it was big query. execute ( ...

 
forum_thread

UserException: Invalid configuration in 'internal' - Check permissions

Hi all,   I have a master/slave code so that each slave reads a subset of points of the same database. ObjectDB entities do not allow serialization and so I have sent, to each slave, the file path. With such information I have tried to create an entityManager, in each slave, as follows: EntityManagerFatory entityManagerFactory = Persistence.createEntityManagerFactory(filePath); EntityManager = entityManagerFactory.createEntityManager(); However I get the following error ... at com.jscilib.jppf.math.data.stats.bin.ComputePCA.main ( ComputePCA. java :129 ) at ... Persistence. java :54 ) at com.jscilib.jppf.data.db.odb.ObjectDBBulkDataset. <init> ( ObjectDBBulkDataset. ... Hi, Following your recmmendations, I have set the objectdb.conf file via System.setProperty("objectdb.conf", ...

 
forum_thread

How to delete M2M relationship?

In user model class I have the following: public class User implements Serializable { ... . CascadeType . ALL ) private Set timeslots = new HashSet ( ) ; And i would ... ex ) { //Rolling back data transactions if ( transaction != null ...

 
forum_thread

How to use JOIN FETCH?

The ObjectDB manual (http://www.objectdb.com/java/jpa/query/jpql/from) gives an example of using JOIN FETCH to avoid excessive round trips to the database: ... an existing system where lots of queries run over the same set of objects, returning different sets of data.  The same relationship will need to be retrieved both eagerly and ...

 
forum_thread

performance limit

Hi, can someone share expirience with performance limits of ObjectDB especialy when quering tables with large records sets. Our issue is with tables with 100.000+ records. Everything was OK when we had few thousand records. We have a simple SELECT statement which selects from a table with 100.000+ records by UserID atribute, tables have from 5 to 20 atributes. Usualy the results range from few hundred to few thousand records. This query takes up to 12 seconds. Is this normal, what when we will have few milion records, how to handle this. ... milion records, how to handle this. Everything is set to lazy loading, we tried indexing the table and it doesnt help much. ... faster in the Explorer (because in the Explorer result data is always loaded lazily). You may execute queries in the application with ...

 
forum_thread

Database connection url

I'd like to run a database called db1.odb on port 6136, and simultaneously open it in the explorer. I left the conf file set as: <server> <connection port="6136" max="100" /> <data path="$objectdb/db-files" /> </server> However, I'm not sure about the connection url for the code, and for the explorer. I tried this: Transactor.emf = Persistence.createEntityManagerFactory ("$objectdb/db1.odb");... open it in the explorer. I left the conf file set as: <server > <connection port = "6136" max = "100" /> <data path = "$objectdb/db-files" /> </server > ...

 
forum_thread

@ElementCollection of type enum

Hi! I have in an entity called User with the following field: @ElementCollection(fetch = FetchType.EAGER) private Set<UserPermission> permissions; package x.x.x.x public enum UserPermission { BASIC, COACH, ADMIN } Use case: there are users which contain the first 2 permissions (BASIC and COACH, so the first 2 entries). ... field: @ElementCollection(fetch = FetchType.EAGER) private Set<UserPermission> permissions; package x. x . x . x ... for example, BASIC231 between BASIC and COACH values, data in ObjectDB will be altered in a way that the users that previously had ...

 
forum_thread

Multitenancy with discriminator

Hello, I have a very large business application that makes use of the Hibernate "Filters" feature and of the EclipseLink "Single Table Multitenancy with discriminator" feature in order to implement entities filtering based on a discriminator. Here is an example of one of my business objects: public class BusinessPartner {     protected String id;     protected Domain domain;     ... } ... Domain mainDomain;     protected Set<Domain> otherDomains;     ... } ... query engine should be able to read some configuration data and when filtering is required for a given entity class it should add an ...