Just before our upcoming release of Q1 2010 SP1 (early next week), I’ve decided to check how RadGridView for WPF will handle complex Entity Framework 4.0 query with almost 2 million records:

public class MyDataContext
{
    IQueryable _Data;
    public IQueryable Data
    {
        get
        {
            if (_Data == null)
            {
                var northwindEntities = new NorthwindEntities();
                var queryable = from o in northwindEntities.Orders
                               from od in northwindEntities.Order_Details
                                select new
                                {
                                    od.OrderID,
                                    od.ProductID,
                                    od.UnitPrice,
                                    od.Quantity,
                                    od.Discount,
                                    o.CustomerID,
                                    o.EmployeeID,
                                    o.OrderDate
                                };
                _Data = queryable.OrderBy(i => i.OrderID);
            }
 
            return _Data;
        }
    }
}

The grid is bound completely codeless in XAML using RadDataPager with PageSize set to 50:

<Window x:Class="WpfApplication1.MainWindow"
 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
 Title="MainWindow" mc:Ignorable="d" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:my="clr-namespace:WpfApplication1" xmlns:my1="clr-namespace:System;assembly=mscorlib">
    <Window.Resources>
        <my:MyDataContext x:Key="dataContext" />
    </Window.Resources>
    <Grid DataContext="{StaticResource dataContext}">
        <Grid.RowDefinitions>
            <RowDefinition />
            <RowDefinition Height="Auto" />
        </Grid.RowDefinitions>
        <telerik:RadGridView x:Name="RadGridView1" ItemsSource="{Binding Data}" />
        <telerik:RadDataPager PageSize="50" Source="{Binding Items,ElementName=RadGridView1}" Grid.Row="1"/>
    </Grid>
</Window>

The result: Blazing fast sorting, paging, grouping and filtering of all data applied directly to the data-base server!