title: In Meteor, how can I query only the records of a given subscription?
body: <p>I understand that a a subscription is a way to flow records into a client-side collection, from <a href="https://stackoverflow.com/questions/12824781/meteor-and-subscriptions">this post</a>, and others...</p>
  
  <p>However, per <a href="https://stackoverflow.com/questions/19826804/understanding-meteor-publish-subscribe/21853298#21853298">this post</a>, You can have multiple subscriptions that flow into the same collection.</p>
  
  <pre><code>// server
  Meteor.publish('posts-current-user', function publishFunction() {
    return BlogPosts.find({author: this.userId}, {sort: {date: -1}, limit: 10});
    // this.userId is provided by Meteor - http://docs.meteor.com/#publish_userId
  }
  Meteor.publish('posts-by-user', function publishFunction(who) {
    return BlogPosts.find({authorId: who._id}, {sort: {date: -1}, limit: 10});
  }
  
  // client
  Meteor.subscribe('posts-current-user');
  Meteor.subscribe('posts-by-user', someUser);
  </code></pre>
  
  <p>Now - I obtained my records via two different subscriptions, can I use the subscription to get to the records that it pulled back? Or must I requery my collection? What is the best practice for sharing that query between client and server?</p>
  
  <p>I hope I'm not missing something obvious here, but executing the <code>Meteor.subscribe</code> function only for its side-effects seems to be losing a very useful piece of information - namely which subscription a record came from. Presumably the names of publications and subscriptions are chosen to be meaningful - it would be nice if I could get to records associated with that name.</p>