title: What is the syntax for MongoDB query for boolean values?
body: <p>The values for the key <code>is_agent</code> is TRUE or blank.</p>
  <p>I have the following query:</p>
  <pre><code>db.users.find( { $not: {is_agent:TRUE} }, {email:1} )
  </code></pre>
  <p>I get the following error:</p>
  <pre><code>ReferenceError: TRUE is not defined
  </code></pre>
  <p>When I used <code>&quot;TRUE&quot;</code> I got the following error:</p>
  <pre><code>&quot;$err&quot; : &quot;Can't canonicalize query: BadValue unknown top level operator: $not&quot;,
  &quot;code&quot; : 17287
  </code></pre>
  <p>What is the correct syntax?</p>