.FILL doesn't working on NULL guid
<p>I've a table like this structure:</p>

<p><a href="https://i.stack.imgur.com/gimbt.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/gimbt.png" alt="enter image description here"></a></p>

<p>now, sometimes, the field: <code>resources_guid</code> could be null, in particular if is NULL I set a value of 0. I'm trying to fill all records in the table using this technique:</p>

<pre><code>Dim local_ds As New DataSet
Dmi query = "SELECT * FROM tables"
MyAdapter = New MySqlDataAdapter(query, my connection)
MyAdapter.Fill(local_ds)
</code></pre>

<p>but when the <code>.Fill</code> method is executed I get this error message:</p>

<blockquote>
  <p>Guid must contain 32 digits with 4 dashes (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"</p>
</blockquote>

<p>How I can solve this?</p>