title: Core Data: does delete an entity remove all relationships of other entities to it?
body: <p>Say if I have two entities: MySubscription and AllSubscription, MySubscription has a one to one relationship to AllSubscription, thus AllSubscription has a inverse relationship to MySubscription, say:</p>
  
  <pre><code>MySub     AllSubs
  a   &lt;---&gt;   A
              B
  c   &lt;---&gt;   C
              D
  e   &lt;---&gt;   E
  </code></pre>
  
  <p>if I delete a, does Core Data automatically set A.mysub to nil?</p>