title: why can't create a new user in mysql?
body: <pre><code>mysql&gt; select user,host from mysql.user;
  +------------------+-----------+
  | user             | host      |
  +------------------+-----------+
  | root             | 127.0.0.1 |
  | root             | ::1       |
  | debian-sys-maint | localhost |
  | developer        | localhost |
  | jack             | localhost |
  | root             | localhost |
  | root             | rebuild   |
  +------------------+-----------+
  7 rows in set (0.00 sec)
  
  mysql&gt; show databases;
  +--------------------+
  | Database           |
  +--------------------+
  | information_schema |
  | mysql              |
  | performance_schema |
  | wpdatabase         |
  +--------------------+
  4 rows in set (0.00 sec)
  
  mysql&gt; CREATE USER wpuser@localhost;
  ERROR 1396 (HY000): Operation CREATE USER failed for 'wpuser'@'localhost'
  </code></pre>
  
  <p>Why can't create a new user in mysql? The user <code>wpuser</code> is not in the table <code>user</code>.
  I neved used databases, so can anyone help me on how to create a new user ?</p>
  
  <p>No,it is not the problem of password(123456 is the key of mysql database).</p>
  
  <pre><code>mysql&gt; CREATE USER 'wpuser'@'localhost' IDENTIFIED BY '123456';
  ERROR 1396 (HY000): Operation CREATE USER failed for 'wpuser'@'localhost'
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/t8zRj.png" alt="enter image description here"></p>
  
  <p>It is so strange ,please go on .</p>
  
  <p><img src="https://i.stack.imgur.com/zzXBb.png" alt="enter image description here"></p>
  
  <p>Why   <code>CREATE USER wpuser@localhost;</code> can't ; <code>CREATE USER wpusers@localhost;</code> can?</p>