title: AWS AppSync: How to listen to change from DynamoDB (not by mutation)
body: <p>I create AppSync API from Amplify Cli for my angular project.</p>
  
  <p>The website can subscribe to OnChangeListner where DynamoDB is updated by mutation. It works.</p>
  
  <pre><code>async ngOnInit() {
  
     this.api.OnUpdateTableListener.subscribe({
        next: resp =&gt; {
          console.log("update !!!");
          console.log("update: " + JSON.stringify(resp));
          let update = resp.value.data.onUpdateTable;
          this.items = this.items.map(function(a) {
            return a.id === update.id ? update : a;
          });
  
        }
      });
  }
  
  
  async update(selectedItem) {
      const update = {
        id: selectedItem.id,
        status: !selectedItem.status
      };
      await this.api.UpdateTable(update);
    }
  </code></pre>
  
  <p>However, I noticed that if I updated DynamoDB manually, the subscription doesn't work at all. </p>
  
  <p>Any suggestion on how to update DynamoDB (not by mutation) and AppSync subscriptions still work.</p>