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Queries are slow on a large database

Hi, I have a 12GB database with 787603 entries. It is much larger than usual and there are performances issues. I am doing small queries and they take much longer than I expect, i.e.: Get the total number of entries Get 25 consecutive entries (i.e. 0-25) Get one specific entry On average each query needs 4 to 5 minutes to return a result. I have been adviced to use indexes but they are already used through the JDO Metadata file. For instance I use this class: ... as the database file is not sufficient. In addition, consider using composite indexes as suggested in #2 above. The sample ...



Welcome to ObjectDB Forum #1 2010-05-13 15:13 Welcome to the new ObjectDB Website and the new ObjectDB Forum! ObjectDB Support Object ...



Used in the mapping of associations.(Annotation of JPA)



Is used to specify the mapped column for a persistent property or field.(Annotation of JPA)


JSON serialization and __odbHidden members

Hi.. Building a REST API (Jersey-based one) I noticed that object object I serialize to JSON has a clone field with "__odbHidden" suffix, e.g.there's  "id" and "id__odbHidden" is also (unwantenly) present with the same value. In general, we can annotate fields to include/exclude them from JSON serialization, but since these fields are not declared in my classes, I have no idea how to tell marshaller to avoid them. #1 2015-10-30 10:13 Hi.. Building a REST API (Jersey-based one) I noticed that every object I serialize to JSON has a clone f ...


Cascading makeTransient

Hi! We have a memory leak in our app because of ObjectDBs __odbTracker fields. The situation is that we read the objects from the DB (many and large objects of class A) and then keep in the application cache only some embedded parts of those objects (let's call them class B). This application cache should work independently on the DB as if it contained transient objects. #1 2015-07-03 10:50 Hi! We have a memory leak in our app because of ObjectDBs __odbTracker fields. The situation is t ...


Step 6: Set the Spring XML

Explains how to set XML in an Eclipse Spring MVC JPA web application project. To integrate the Spring Framework into a web application we have to add the definition of the Spring dispatcher servlet to the  web.xml configuration file and to configure that servlet using another xml configuration file. Open the  web.xml ...



This is the root of all JDO Exceptions.(Exception of JDO)


JPA 2 Annotations

Reference (JavaDoc) of all the JPA 2 annotations, including @Entity, @Embeddable, @NamedQuery, @GeneratedValue, etc. JPA defines dozens of annotations that can be divided into the following groups: Annotations for JPA aware classes: JPA Annotations for Classes JPA Annotations for JPQL Queries Annotations for fields in JP ...


Using your own classes in the entity class?

When I use other objects from other self-made classes in the JPA Entity Class I get the following error code: #1 2016-02-08 14:48 This post is solved edit delete ...