title: Entity Framework: Filtering by multiple conditions on sub table
body: <p>Lets say there are two tables - Customers and CustomerConfigurations.</p>
  
  <p>Customer contains ID,NAME</p>
  
  <p>CustomConfigurations contains CustomerID, Type(int), Value(int)</p>
  
  <p>I want to get all customers that ALL the following conditions apply to:</p>
  
  <ol>
  <li><p>Has a customerconfiguration row with type=x and value=x1</p></li>
  <li><p>Has a customerconfiguration row with type=y and value=y1</p></li>
  <li><p>Has a customerconfiguration row with type=z and value=z1</p></li>
  </ol>
  
  <p>You get the point.</p>
  
  <p>What is the best way to achieve such a query with entity framework?</p>