title: SQL Server: Optional variable in a stored procedure
body: <p>I would like to know if there is anyway I can set one of my stored procedure parameter as optional.</p>
  
  <pre><code>IF @thing_id &lt;&gt; ''
  BEGIN 
   SET @sFiltre = @sFiltre + ' AND OPERES.OPE_THING = ' +  CONVERT(VARCHAR,@thing_id)
  END
  </code></pre>