title: SQL code in an update query
body: <p>Once again Im stuck on the same database. This time Im creating an update query that removes 1 of each part in a table when a button is pressed. But when a part is already at 0 it goes to -1. How can I stop this from happening?</p>
  
  <p>I used SQL to achieve this,</p>
  
  <pre><code>UPDATE [ASM-00065 WIP] 
  SET [ASM-00065 WIP].[Current Stock] = [ASM-00065 WIP]![Current Stock]-1;
  </code></pre>