db4o Developer Community

Good news for everybody who loves to be on the bleeding edge but hates fighting with SVN, Ant and other infrastructure tools to roll a build of their own: We have set up CruiseControl to provide fresh snapshots of the current SVN state every few hours. They are available for download here. The generated files currently include db4o core for ...

When we review db4o applications we almost always find possibilities how to improve performance with one or two db4o configuration calls. In some cases it is possible that the db4o engine itself gives helpful suggestions (''This query is not running against an indexed field.''). We have developed a new feature for this purpose, we call it ...

Because of an incompatibility with our new marshalling format, we decided to drop the old encryption mechanism: Db4o.configure().encrypt(boolean flag) Db4o.configure().password(String password) The underlying functionality is from ancient db4o times and not completely safe against intrusion. In the meanwhile we supply an excellent new safe and ...

Another bastion fell few days ago. Rodrigo managed to switch our SCM from the good old' CVS to a fresh new SVN. As far as we can tell, everything went smoothly thanks to the cvs2svn script developed by the SVN folks. If you were used to checkout the sources from our CVS, be sure to read the Source Code Access page to migrate. Isn't it ...

You may have read the blog posts about BTrees, and the new marshallers for strings and untyped references. Here is the big picture: http://www.db4o.com/downloads/db4oPolePosition.pdf The above Poleposition results document the recent progress in performance very well. The db4o versions in the PDF are a bit hard to understand. Here is the ...

As already posted in the string marshaller blog entry db4o 5.4 comes with a completely rewritten marshalling format. We did another huge change that may even be more significant for many applications: All objects referenced by untyped references (java.lang.Object / System.Object) and all typed and untyped arrays are now ...

We have revised the way we do String marshalling. We now make sure that all strings are stored along with their parent objects, in the same slot. Doing this change was not all easy. We had to change the way slot lengths are calculated since all slots are now of variable length, whereas we could use fixed lengths for first class objects ...

We have written a completely new BTree architecture for this release. It is designed to be used for all indexes in db4o: - Class Indexes - Field Indexes - Freespace Management - Fast huge Collections - Indexed Collections For now (5.4 development release) the new BTrees are only being used for Class Indexes. The advantages in comparison to our ...

ObjectManager 1.8 is available from the db4o Downloadcenter, and is designed to work with db4o V5.3. Class aliases have been used to enhance ObjectManager 1.8, the db4o database browser, such that ObjectManager (a Java application) is able to browse .NET databases -- a nice demonstration of crossplatform capabilities. ObjectManager 1.8 also ...

db4o 5.3 (development version) is available from the db4o downloadcenter. The new alias feature to translate classes, namespaces and package names between application and database opens a wide range of usecases. Here are some examples: // Creating an alias for a single class Db4o.configure().addAlias( new TypeAlias(''com.f1.Pilot'', ...