<div class="content" name="GetSystemChangeNumber" uuid="8ccdd400-cf13-4747-8ddb-77b1a0b6de79"><p>The GetSystemChangeNumber method returns the number of
changes made to data since the <a href="1243ba70-74ca-44f9-be0b-dfd6697010b4#gt_086b13f2-2715-4000-a16c-6acc3d59cc19" data-linktype="relative-path">metabase</a> was created.</p><dl>
<dd>
<div><pre> HRESULT GetSystemChangeNumber(
   [out] DWORD* pdwSystemChangeNumber
 );
</pre></div>
</dd></dl><p><b>pdwSystemChangeNumber: </b>A pointer to an
unsigned 32-bit integer value containing the system change number. This number
is increased each time the metabase is updated. </p><p><b>Return Values: </b>A signed 32-bit value that
indicates return status. If the method returns a negative value, it failed. If
the 12-bit facility code (bits 16–27) is set to 0x007, the value contains a
Win32 error code in the lower 16 bits. Zero or positive values indicate
success, with the lower 16 bits in positive nonzero values containing warnings
or flags defined in the method implementation. For more information about Win32
error codes and <a href="../ms-dtyp/a9046ed2-bfb2-4d56-a719-2824afce59ac" data-linktype="relative-path">HRESULT</a>
values, see <a href="../ms-erref/1bc92ddf-b79e-413c-bbaa-99a5281a6c90" data-linktype="relative-path">[MS-ERREF]</a>.</p><dl>
<dd>
<table><thead>
  <tr>
   <th>
   <p>Return value/code</p>
   </th>
   <th>
   <p>Description</p>
   </th>
  </tr>
 </thead><tbody><tr>
  <td>0x00000000 S_OK</td>
  <td>The call was successful.</td>
 </tr></tbody></table>
</dd></dl><p>The <a href="1243ba70-74ca-44f9-be0b-dfd6697010b4#gt_e127848e-c66d-427d-b3aa-9f904fa4ada7" data-linktype="relative-path">opnum</a>
field value for this method is 22. </p><p>When processing this call, the server MUST do the following:</p><ul><li><p><span><span> 
</span></span>Return the current system change number in the <i>pdwSystemChangeNumber</i>
parameter. The system change number is a 32-bit unsigned integer value that is
incremented when a change is made to the metabase. This value SHOULD be
persisted between metabase sessions.<a id="Appendix_A_Target_16"></a><a aria-label="Product behavior note 16" href="88fd1df0-e63e-41ca-9bf3-bedcab57cd86#Appendix_A_16" data-linktype="relative-path">&lt;16&gt;</a></p>
</li></ul></div>