title: How do I use substring in WHERE clause?
body: <p>My expression in OpenSQL is:</p>
  
  <pre><code>SELECT * FROM  J_1BNFLIN  AS B
    WHERE SUBSTRING(REFKEY , 1 , 10 )
  </code></pre>
  
  <p>The substring portion of the where clause is not working. What am I doing wrong?</p>