title: Cloudkit query array size == 0
body: <p>I'm performing query operation with Cloudkit, my record type is like this:</p>
  
  <pre><code>CKRecord Type: Person
  {
    name STRING,
    age  INTEGER,
    friends  ARRAY,
  }
  </code></pre>
  
  <p>Now, I want to query all person with no friends.I have tried</p>
  
  <pre><code>NSPredicate *predicate = [[NSPredicate alloc] initWithFormat: @"friends[SIZE] == 0"];
  CKQuery *query = [[CKQuery alloc] initWithPredicate: predicate];
  </code></pre>
  
  <p>And</p>
  
  <pre><code>NSPredicate *predicate = [[NSPredicate alloc] initWithFormat: @"friends.@count == 0"];
  CKQuery *query = [[CKQuery alloc] initWithPredicate: predicate];
  </code></pre>
  
  <p>The first one crashed with warning </p>
  
  <blockquote>
    <p>friends[SIZE] is not an evaluated object expression</p>
  </blockquote>
  
  <p>and second one returning error of </p>
  
  <blockquote>
    <p>Invalid predicate</p>
  </blockquote>
  
  <p>So , what is the correct way to query with array size?</p>