title: how to find values between a range in mongodb
body: <p>I have a db named <strong>student</strong> and I want to select the values between 30 and 60 from a column named u1. This is the query I used,but it shows some error</p>
  
  <pre><code>db.student.find($and:[{u1:{$gt:30}},{u1:{$lt:60}}])
  </code></pre>