title: Cannot use the "not equal" operator when querying for a collection in AngularFire
body: <p>I am trying to pull a collection from Firebase that is not associated to the user. So far, I've successfully queried for the user's collection, but I can't seem to get the collection that is not associated with the user using the <code>!=</code> operator. </p>
  
  <p>Here's my code:</p>
  
  <pre><code>  // Does not work!
    eventCollection: AngularFirestoreCollection&lt;Event&gt; = this.angularFirestore.collection("events", ref =&gt;
      ref.where("uid", "!=", this.firebaseAuth.auth.currentUser.uid)
    );
    eventCollection$: Observable&lt;Event[]&gt; = this.eventCollection.valueChanges();
  
    // Works!
    myCollection: AngularFirestoreCollection&lt;Event&gt; = this.angularFirestore.collection("events", ref =&gt;
      ref.where("uid", "==", this.firebaseAuth.auth.currentUser.uid)
    );
    myCollection$: Observable&lt;Event[]&gt; = this.myCollection.valueChanges();
  </code></pre>
  
  <p>The error that's thrown is: </p>
  
  <pre><code>ERROR in src/app/event/events.service.ts(35,22): error TS2345: Argument of type '"!"' is not assignable to parameter of type 'WhereFilterOp'.
  </code></pre>
  
  <p>I tried looking for a logical operator that corresponds to <code>!=</code>, but can't seem to find it.</p>
  
  <p>Any help would be greatly appreciated!</p>