title: List all the customers who are not active, with MySQL
body: <p>I have complicated questions that need your help:</p>
  <p>Q: List all the customers who are not active.</p>
  <ul>
  <li>Customer table: customerid, name, address....</li>
  <li>Mobile table: customer id, mobileid, status (Null and Cancelled date)</li>
  </ul>
  <p>How to write the SQL query to check who is the customers not active based on status?</p>