title: JOIN the same statement without WHERE clause
body: <p>I have the following table:</p>
  
  <pre><code>CREATE TABLE posts...
  id INT(11),
  time DATETIME,
  ...
  </code></pre>
  
  <p>And I want to know the highest ID in general, and I also want to know the latest post disregarding posts from the  last hour so I can subtract them to get the number of posts from the past hour.</p>
  
  <p>I could do two queries:</p>
  
  <pre><code>SELECT MAX(id) AS old_max FROM posts WHERE time &lt; 
      DATE_SUB(NOW(), INTERVAL 1 HOUR);
  </code></pre>
  
  <p>And</p>
  
  <pre><code>SELECT MAX(id) AS max FROM posts;
  </code></pre>
  
  <p>But I'd like to have them in the same result set. How would I achieve this?</p>