title: Mysql "where" and "or" statement
body: <p>I started to work on a Mysql query abut it keeps coming up with a error? </p>
  
  <p>can some one look at it and tell me what i am doing wrong? </p>
  
  <pre><code>$query = ("select * from `users` where (`username`='$username' and `password`='$password' or select * from `users` where `$username `='$email' and `password`='$password')");
  </code></pre>
  
  <p>the error is</p>
  
  <pre><code> mysql_num_rows(): supplied argument is not a valid MySQL result resource in /home/a8423624/public_html/testchecklogin.php on line 57
  </code></pre>
  
  <p>which means that it hasn't found anyone. This means that my Query is wrong?</p>