Return a paged result from custom data provider plugin

Hello!

I've just got started with virtual entities and custom data provider. I made my own data provider and are fetching results from an external database. But the result is huge and I have to implement paging mechanism.

I'm guessing Dynamics is telling me that thru the context:

var context = (IPluginExecutionContext)serviceProvider.GetService(typeof(IPluginExecutionContext));

object queryObject = null;
if (context.InputParameters.TryGetValue("Query", out queryObject))
{
  var query = queryObject as QueryExpression;
  ...
}

I can get WHAT it wants, but how do I return the data say page 3 of it? Or that "here is data, its 50 elements on page 3 of 6"?