About addition


Delete me

Can someone please tell me what I'm doing wrong here? public List<Person> read(String name, ServletContext servletContext) {         EntityManagerFactory emf = (EntityManagerFactory) servletContext.getAttribute("emf");         EntityManager em = emf.createEntityManager();         List<Person> allPersons;         try { #1 2014-04-18 13:03 Please delete this comment edit delet ...


Cache usage

after a runtime of several weeks we are now analyzing the usage of the cache and so on. Looking at the heap dump we suspect that the cache is really used (see heap dump attached), the RAM allocated by objectdb is much less than we would expect. The database file has around 25 GByte of size and there is heavy traffic of around 400 clients communicating permanently via webSockets to the objectdb. The config is attached as well. The question is: is the cache really used ? ... periodically and 70% of the maximum size is normal. In addition to this cache, the OS manages its own cache and can use all the free ...


Show Sql/Jpql

Is there a way to show the executed Sql/Jpql in the console? ... all the logging information is written to the console, in addition to being written to the log file. Currently you cannot send only ...


Partial Indexing

I have a question about partial indexing. For example, a field of String type ttt, will be distinguished by the first 5 characters, then I can make a index of substr(ttt,1,5) in MySQL. With ObjectDB, how can I write the annotation for this purpose? TIA Institute of Computer Technologies #1 2011-05-22 12:24 I have a question about partial indexing. For example, a field of String type ttt, will be distinguished ...


Database File Encryption

ObjectDB supports encryption of client-server communication over the network using SSL. Encryption of data in database files is less commonly used, since it slows the database, and when necessary, external encryption is possible (e.g. at the operating system level). Still, this might be useful for some applications.... is less commonly used, since it slows the database. In addition, when necessary, external encryption can be used (e.g. at the ...


ObjectDB Roles and Groups

Hello, How can I incorporate roles/group in ObjectDB config file? I see no support for this. For example, I would like to place several users under a given group or role, but I see no way of doing this as no such element is present  in the config file. Is it possible to have this? ... to support inheritance from other virtual users (in addition to $default ) in next versions - will this help? If you ...


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 ...



(Optional) Unique constraints that are to be placed on the table.(Annotation Element of javax.persistence.JoinTable)



Thrown by the persistence provider when a transaction is required but is not active.(Exception of JPA)


Cascading (persist) with a mix of enhanced and not enhanced entities

We find out that it is actual not possible to use enhanced and not enhanced entities together. Exist any limitations regarding the use of enhanced and non-enhanced entities? We work based feature and want to load other bundles as an artifact from the Nexus. These are always enhanced. To enhance the entities during development is, because of our build environment, very time-consuming. Unfortunately, we can not reproduce this with a small example until now. Sometimes it works. ... of enhanced classes must also be enhanced." In addition, although not specified in the manual, if a class is enhanced, its ...