title: My PHP username line is not checking if the username already exist in my db
body: <p>I used this line of code to check if the username already exist in my database, if the user does not exist it creates it- if it does <code>echo 'username already exist'</code></p>
  
  <pre><code>if(!DB::query('SELECT username FROM users WHERE username=:username', array(':username'=&gt;$username))){
      //create user
      DB::query('INSERT INTO users VALUES (null, :username, :password, :email)', array(':username'=&gt;$username, ':password'=&gt;password_hash($password, PASSWORD_BCRYPT), ':email'=&gt;$email));
      echo "SUCCESS!";
  } else {
      echo 'USER ALREADY EXIST';
  }
  </code></pre>