About ORDER BY

api-jpa

javax.persistence.RollbackException

Thrown by the persistence provider when EntityTransaction.commit() fails.(Exception of JPA)

 
release

2.7.2

... Fixed a bug in displaying inverse (mapped by) relations in the Explorer. Fixed a bug in reusing database ... include META-INF/MANIFEST.MF as the first entry (required by Apache Karaf ). Fixed a cache bug in repeating ...

 
api-jpa

javax.persistence.EntityExistsException

Thrown by the persistence provider when EntityManager.persist(Object) is called and the entity already exists.(Exception of JPA)

 
api-jpa

javax.persistence.JoinColumn

Specifies a column for joining an entity association or element collection.(Annotation of JPA)

 
forum_thread

JPA and handling large data sets

This is not a rellay ObjectDB problem, rather a JPA problem. Our web-based DB supports Hibernate or JPA (ElicpseLink/ObjectDB). We implemented a export/import class to export the whole database or single datasets (domains) in a persistence layer/database independent format. This class works fine - DB exports form a Hibernate/MySQL base via the independent formt to ObjectDB is possible. But exporting large binary data sets is very slow. To avoid memory problems the binary data type is read step by step during the export with the  query/setFirstResult() & setMaxResults().... To avoid memory problems the binary data type is read step by step during the export with the  query/setFirstResult() & ... For example, if your query returns results ordered by the primary key, use the value of the primary key of the last object in one ...

 
api-jpa

javax.persistence.LockTimeoutException

Thrown by the persistence provider when an pessimistic locking conflict occurs that does not result in transaction rollback.(Exception of JPA)

 
release

2.7.1

... include META-INF/MANIFEST.MF as the first entry (required by Apache Karaf ). Fixed a cache bug in repeating ... page sizes larger than 64KB (which are not supported by ObjectDB). Fixed an issue of very slow online backup. ...

 
forum_thread

Query perfromance problem

Hi, I was playing with paging and sorting recently and after trying few different aproaches got some strange behavior from ODB. First of all, I will show you results from page rendering times, but trust me - when debugging application, getting data from ODB takes a long time in one case. Anyway, one of my methods in DAO looks like this: ... q = "select prod from Product prod order by prod." + sortColumn + " ASC" ; } else ... q = "select prod from Product prod order by prod." + sortColumn + " DESC" ; } icQuery ...

 
forum_thread

100% CPU when using multiple BETWEEN

Hi, we are evaluating ObjectDB 2.5.1_03 in embedded mode. We have a DB of about 2800 instances of a class that has two java.lang.String members: toExtension and fromExtension. There are other members in the class, but not relevant to the problem.   A query like this cause the java process to start running at 100% CPU (endless loop) and it never recovers: ... AND '2002' ) ) ) ORDER BY r . startDate DESC , r . startTime DESC , r . ... AND '2099' ) ) ) ORDER BY r . startDate DESC , r . startTime DESC , r . ...

 
forum_thread

composite index not used in query

we defined a composite index for class Action: @Index(name="ssst",members={"startDate","state","subType","type"}) and an index for the OneToMany @OneToMany(fetch=FetchType.LAZY) @Index  public List<ObjectNode> objectsInCharge = new ArrayList<ObjectNode>(); on running a query like ... Avoid overflow of published source code examples by breaking long lines . You may mark in paragraph code words ... names) with the code style (can be applied by ctrl + D). Long stack traces (> 50 lines) and complex ...