Showing posts from August, 2011

WCF Ria Services result set size limitation

While creating what should be a simple silverlight WCF RIA services application, the client returned the following error for some datasets:

System.ServiceModel.DomainServices.Client.DomainOperationException: Load operation failed for query 'GetBins'. Value cannot be null.
Parameter name: validationErrors ---> System.ArgumentNullException: Value cannot be null.

By using firebug and limiting the size of the return dataset, it became evident that after a certain size, the dataset wasn't returned at all with the http package.
It turns out that this is a WCF RIA services configuration issue. The default value for MaxItemsInObjectGraph was something way below the total number of records returned.
The solution was to do one of two things: Set MaxItemsInObjectGraph to be some larger number either in the web.config, or in the domain service class definition itself as follows:

[ServiceBehavior(MaxItemsInObjectGraph = 2147483647)]
public class myDomainService : DomainService { ..…