title: How to implement graphQL sub-query
body: <p>I'm having a block trying to figure out the syntax for a query condition that seems like it would be a pretty common one.  </p>
  
  <p>The typedef below stores an ID value for the agent who represents an Author, in a one-agent-to-many (authors) relationship.  I'd like to extract the name of the agent at the same time I'm getting details from the Author schema.</p>
  
  <pre><code>type Author {
      id: ID!
      firstName: String
      middleInitial: String
      lastName: String
      posts: [Post]
      agent: ID
  </code></pre>
  
  <p>}</p>
  
  <p>So the enclosing query (returning a list of all Authors) looks like this:</p>
  
  <pre><code>{
    authors {
      firstName
      lastName
      agent
      }
  }
  </code></pre>
  
  <p>This gives me back the Agent's ID.  How can I use that same query to fetch the agent's name, from a typedef similar to the one above?</p>