title: Does dynamodb global replace the whole item during sync?
body: <p>When enabling dynamodb global table, if there are two writes happens on the same item but different attributes on the table in each region. How does dynamodb sync between these two tables?</p>
  <p>For example, in regionA, there is an update on an item:</p>
  <pre><code>{
    a: 1
  }
  </code></pre>
  <p>at the same time, there is another write on the same table in regionB with below change:</p>
  <pre><code>{
    b: 1
  }
  </code></pre>
  <p>will dynamodb global table sync combine the attributes into one:</p>
  <pre><code>{
   a: 1,
   b: 1
  }
  </code></pre>
  <p>or will one replace the other?</p>