db4o Developer Community

Yes, that's explained here (also for .NET): http://developer.db4o.com/Resources/view.aspx/Reference/Tuning/Native_Query_Optimization Best.

patrick_roemer:by pointers in one direction (db4o SODA allows you to pose queries that traverse references in the opposite direction)Please can you put an example of such kind of query (opposite direction..)? And with the use of collections to implement relations, can db4o look into a collection looking for a candidate (for example with SODA) ...

Hello, I'm using Native Queries and I am very confused with the optimization process, because something like the following query can't be optimized:    Dim etiquetas3 As IList(Of Etiqueta) = BD.Contenedor.Query(Of Etiqueta)(AddressOf QueryEtiquetas)     Public Shared Function QueryEtiquetas(ByVal et As Etiqueta) As ...

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 ...

Ening:Danke für deine Hilfe!! Ich habe Doku gelesen. Leider habe ich trotzdem nicht kopiert, wir ich das praktisch realisieren kann, dass NQ-Abfrage im C/S - Modus in SODA konvertiert werden.  Wenn Deine NQ falsch interpretiert werden, liegt es wohl, wie bereits von Maik beschrieben, daran, dass die Klassen auf dem Server nicht bekannt ...

mjablonski:bloat.jar und db4onqopt.jar brauchst Du natürlich nicht, wenn Du in der .NET-Welt lebst...  ..aber dafür die NQ, Instrumentation, Cecil und FlowAnalysis dlls. Sowohl für Java als auch .NET braucht man die zusätzlichen Libs aber nur für optimierte NQ. Sollte eigentlich hier beschrieben ...

Hello Origon45, First of all thank you very much for your detailed answer :) Some of the things you said already helped us a bit, and your answer was encouraging.   If you don't mind, I would like to explain again how why are using db4o. We are only using it as a backup mechanism to write memory objects to disk. We create a database file, ...

Hi there! Beeing new to OOP and OODB, i have a question regarding to designing an oo database: Assume you have a class ''car''. A user should be able to create/derive some kind of ''prototype instances'' or ''prototype classes'', like mazda-xyz, bmw-m9 and so on with a gui. But at the same time there shold be instances to be generated ...

Using db4o 6.4 for java, with single user .yap file or in-memory adapter (i.e., still no c/s).I do have the nqopt and bloat jars on the classpath in ant build file:   <property name=''thirdParty.lib.dir'' location=''${masterbuild.dir}/thirdParty/lib'' description=''dependencies jars'' />  <!-- OO database -->  ...