db4o Developer Community

One other tip to get more performance in queries would be to use ''lazy queries'': http://developer.db4o.com/Resources/view.aspx/Reference/Object_Lifecycle/Querying/Query_Modes but this lazy mode has pros and cons (you should check them in the page above). I do not know the shape of you project class but if it has members which are collections ...

Carl Rosenberger: Activation is done by using very fast internal pointers. No queries are executed when activation happens.  Thanks for the clarification, it helps answer the original question.  Does activating operations still block like queries and commits? Carl Rosenberger: I am sure we will provide a couple of different ...

Seems this post is more of a ''Product Developer'' than ''User'' forum topic.  Carl Rosenberger: You have to differentiate between Lazy Queries and Lazy Activation: Differentiating makes sense to a point, I do agree that they are different features, so the answer to my question is that .Activate() is not leveraging lazy queries ...

Are lazy queries only utilized when you query for a specific collection of objects directly?  If so, I'd like to see if it can be leveraged for all collections that are activated.  See my use case below...I belive this extention makes a lot of sense for activated collections.  Example use case, while ...

If you use lazy queries, you can stop iterating through the ObjectSet after the first 1,000 objects: http://developer.db4o.com/blogs/product_news/archive/2006/11/10/lazy-queries.aspx  

How do you write a fast program? Easy: It should only do what is absolutely necessary with the smallest number of steps possible. Isn't that ultimate laziness? Lazy == Fast ! With this idea in mind we were looking for ways to do less work in our query processor and to empower your application to be able to tell db4o to do less work. The solution ...

COR-209 is done. Snapshot and Lazy modes are implemented. They work good. Here are first test results from a Poleposition run that I created especially to demonstrate this nice new feature: http://www.db4o.com/downloads/PpCOR-209.pdf I will blog about the feature in detail in the next two or three days.

...and yes, Eric, server-side configurable snapshots to load the full index at once does make sense. That's actually really easy to implement, the new HybridQueryResult already has the functionality to do this with just one call. Good suggestions! I think we want another configuration switch and I think we want the client to manage on a ...

Carl Rosenberger:Lazy queries are now fully functional to be tested. The behaviour is optional and it is not turned on by default. The following configuration switch turns lazy queries on: Db4o.configure().lazyQueryEvaluation(true); I forgot to mention one point: In a C/S setup the client configuration determines if queries are to be executed ...

Since we have people that want to see the C/S version of lazy queries perform well, it was the obvious decision to take C/S on first. Thanks for pointing that out Travis! Lazy queries are now fully functional to be tested. The behaviour is optional and it is not turned on by default. The following configuration switch turns lazy queries ...