title: Need help in a login sequence diagram
body: <p>hi everyone i'm à newbie in uml and my question is simple:i want to draw a sequence diagram for members login and the steps are as follows:</p>
  
  <hr>
  
  <p>the member visits the login page</p>
  
  <p>enters email/pwd</p>
  
  <p>clicks login</p>
  
  <p>then the system goes to the database</p>
  
  <p>if record exists </p>
  
  <p>if account active</p>
  
  <pre><code>  display login success msg 
  </code></pre>
  
  <p>else (account not active) </p>
  
  <pre><code>  display error msg
  </code></pre>
  
  <p>else(record does not exists) </p>
  
  <p>display error msg</p>
  
  <hr>
  
  <p>and the diagram should contains the following objects:</p>
  
  <ul>
  <li><p>member</p></li>
  <li><p>login page</p></li>
  <li><p>System</p></li>
  <li><p>database</p></li>
  </ul>
  
  <p>so can any one show me how it's done and thanks in advance.</p>