blic class _001_merge_first_and_last_name_to_fullname_field : IMigration
{
    public Task UpgradeAsync()
    {
      return DB.Update&lt;Author&gt;()
               .Match(_ =&gt; true)
               .WithPipelineStage(&quot;{$set:{FullName:{$concat:['$Name',' ','$Surname']}}}&quot;)
               .ExecutePipelineAsync();
    }
}
</code></pre>
<h4 id="rename-a-property">Rename a property</h4>
<pre><code class="lang-csharp">public class _002_rename_fullname_to_authorname : IMigration
{
    public Task Upg