db4o Developer Community

Hello. I have some problem with db file.I'm using db4o in my application written in Java.User which uses it broke db file. I know that he updated application (replaced .jar file).New version of app has the same version db4o and the same settings.What was the immediate cause of this problem I don't know. But I have assumption, that he replaced .jar ...

Hello! I'm doing some web services that use an embedded form of BD in db4o. When I make the request to a service any of the place, I create a static object ObjectServer for all services can use to access it, that is, the object instance in the form of BD Singleton. All services are functioning correctly if I go either locally or ...

 Hi, I tried using the db4o defrag functionality on my database file, but sadly it failed. I can't make any sense from the exception. My log file looks like this: 06-Oct-2008 18:07:18 tvadb.database.Db4oFileDefrag openDatabaseINFO: Getting default db4o Configuration...06-Oct-2008 18:07:18 tvadb.database.Db4oFileDefrag openDatabaseINFO: ...

Hi, I have another issue with the client-server environment. It seems that the connection between my client and the db4o server are never actually closed. This soon causes a ''Too many open files'' Exception on my system. I'm using the db4o 6.4 version 6.4.54.11278, both the client and the server run on the same machine (all using Java 1.6 / ...

Hi, I've been evaluating db4o for a client-server environment for the last few weeks. I've been running into a few problems, but could solve most of them using the tutorial, the db4o reference or by looking up in the forum. But I now have an issue that may or may not be a bug, so I thought I'd ask directly for some advice. Of course it could very ...

Hello,The heap space is exhausted when trying to save 1 000 000 simple objects (using Db4oList.add()), whereas a simple Vector still works fine. What is the reason for this and how can I avoid it?Thanks!Zsolt

Hi there,   I am building an application running on db4o 6.4.38.10595 and Java 1.6.02 and I encounter problems regarding Native Query optimization. I added a DiagnosticToConsole-listener which gives me the following error message: :: db4o 6.4.38.10595 Diagnostics ::  Native query not present. :: Native Query Optimizer could not be ...

Hi all.   I have a problem with storing java.sql.Timestamp in the database. Im using java 1.4. and db4o 6.4. ..... db4o- tools, -java1.2, -nqopt and -taj.   The problem is... im using a client/server model. I have applied the fix i need to do ( objectClass( Date.class ).storeTransientFields( true ) ) to both client and server, but ...

Thanks a lot Goran! I added the Diagnostic... Configuration configuration = Db4o.newConfiguration();configuration.diagnostic().addListener(new DiagnosticToConsole());...and noticed a reference to db4o-6.4.38.10595-npopt.jar was missing. Now it works well. Manuel

Hi everyone, I am a newbie. I am trying to use db4o to replace Hsqldb which we are using. And my use case is very simple. The DB only needs to store one type of object -- Employee. class Employee {    // id     // name     // ... other fields } However, the query speed is very slow ...