MS Access Query : Check if form is open / Check if parameter requires input
<p>I'm currently trying, in a MS Access Query (using the GUI tool, and not the SQL tool), to check if a specific form is open or not, without using VBA.</p>

<p>Using the following expression :</p>

<pre><code>Expr1 : [Formulaires]![Form1].[Visible]
</code></pre>

<p>If Form1 is open, the query works fine, but if Form1 is closed, it asks for input, since the Form1 isn't open, and the variable doesn't exist anymore.</p>

<p>Is there a way to check if a specific form is open, or to check if a certain variable requires input ?</p>