SQL Server 2016 - Dynamic Data Masking (DDM)
<p>Does anyone know if DDM has to be enabled before it can be used (and if so how), or are there only certain versions of SQL Server 2016 that have this functionality as trying to run:</p>

<pre><code>ALTER Table Employee
ALTER COLUMN NAME ADD MASKED WITH (FUNCTION='DEFAULT()')
</code></pre>

<p>results in the following error:</p>

<blockquote>
  <p>Msg 534, Level 15, State 100, Line 4 'ADD MASKED' failed because it is
  not supported in the edition of this SQL Server instance
  'DELL-001\SQLEXPRESS01'. See books online for more details on feature
  support in different SQL Server editions.</p>
</blockquote>

<p>The version of SQL I have installed is:</p>

<blockquote>
  <p>Microsoft SQL Server 2016 (RTM-GDR) (KB3194716) - 13.0.1722.0 (X64)<br>
  Sep 26 2016 13:17:23   Copyright (c) Microsoft Corporation  Express
  Edition (64-bit) on Windows 10 Home 6.3  (Build 14393: )</p>
</blockquote>

<p>Thanks!</p>